llm - Man Page

Examples (TL;DR)

Name

llm — LLM documentation

[image: GitHub repo] [image]
<https://github.com/simonw/llm> [image: PyPI] [image]
<https://pypi.org/project/llm/> [image: Changelog] [image]
<https://llm.datasette.io/en/stable/changelog.html> [image: Tests] [image]
<https://github.com/simonw/llm/actions?query=workflow%3ATest> [image: License] [image]
<https://github.com/simonw/llm/blob/main/LICENSE> [image: Discord] [image]
<https://datasette.io/discord-llm> [image: Homebrew] [image]
<https://formulae.brew.sh/formula/llm>

A CLI tool and Python library for interacting with OpenAI, Anthropic’s Claude, Google’s Gemini, Qwen, Gemma, Kimi, DeepSeek, Mistral, and dozens of other Large Language Models, both via remote APIs and with models that can be installed and run on your own machine.

Watch Language models on the command-line <https://www.youtube.com/watch?v=QUXQNi6jQ30> on YouTube for a demo or read the accompanying detailed notes <https://simonwillison.net/2024/Jun/17/cli-language-models/>​.

With LLM you can:

Quick Start

First, install LLM using pip or Homebrew or pipx or uv:

pip install llm

Or with Homebrew (see warning note <#homebrew-warning>):

brew install llm

Or with pipx <https://pypa.github.io/pipx/>:

pipx install llm

Or with uv <https://docs.astral.sh/uv/guides/tools/>

uv tool install llm

Use LLM to run prompts or start chats against an arbitrary OpenAI-compatible Chat Completions endpoint, such as LM Studio <https://lmstudio.ai>​. With uvx, you can do this without installing LLM first:

uvx llm openai endpoint http://localhost:1234/v1 \
  -m google/gemma-4-12b \
  "What is the capital of France?"

uvx llm openai endpoint http://localhost:1234/v1 \
  -m google/gemma-4-12b \
  --chat

Add --key your-api-key if the endpoint requires authentication. See Run against an endpoint without configuring it <#openai-endpoint> for more options.

If you have an OpenAI API key <https://platform.openai.com/api-keys> key you can run this:

# Paste your OpenAI API key into this
llm keys set openai

# Run a prompt (with the default gpt-5.6-luna model)
llm "Ten fun names for a pet pelican"

# Extract text from an image
llm "extract text" -a scanned-document.jpg

# Use a system prompt against a file
cat myfile.py | llm -s "Explain this code"

Run prompts against Gemini <https://aistudio.google.com/apikey> or Anthropic <https://console.anthropic.com/> with their respective plugins:

llm install llm-gemini
llm keys set gemini
# Paste Gemini API key here
llm -m gemini-3.5-flash 'Tell me fun facts about Mountain View'

llm install llm-anthropic
llm keys set anthropic
# Paste Anthropic API key here
llm -m claude-sonnet-5 'Impress me with wild facts about turnips'

You can also install a plugin <#installing-plugins> to access models that can run on your local device. If you use Ollama <https://ollama.com/>:

# Install the plugin
llm install llm-ollama

# Download and run a prompt against the Orca Mini 7B model
ollama pull llama3.2:latest
llm -m llama3.2:latest 'What is the capital of France?'

To start an interactive chat <#usage-chat> with a model, use llm chat:

llm chat -m gpt-4.1
Chatting with gpt-4.1
Type 'exit' or 'quit' to exit
Type '!multi' to enter multiple lines, then '!end' to finish
Type '!edit' to open your default editor and modify the prompt.
Type '!fragment <my_fragment> [<another_fragment> ...]' to insert one or more fragments
> Tell me a joke about a pelican
Why don't pelicans like to tip waiters?

Because they always have a big bill!

Project News

For everything else, see the llm tag <https://simonwillison.net/tags/llm/> on my blog.

Contents

Setup

Installation

Install this tool using pip:

pip install llm

Or using pipx <https://pypa.github.io/pipx/>:

pipx install llm

Or using uv <https://docs.astral.sh/uv/guides/tools/> (more tips below):

uv tool install llm

Or using Homebrew <https://brew.sh/> (see warning note):

brew install llm

Upgrading to the latest version

If you installed using pip:

pip install -U llm

For pipx:

pipx upgrade llm

For uv:

uv tool upgrade llm

For Homebrew:

brew upgrade llm

If the latest version is not yet available on Homebrew you can upgrade like this instead:

llm install -U llm

Using uvx

If you have uv <https://docs.astral.sh/uv/> installed you can also use the uvx command to try LLM without first installing it like this:

export OPENAI_API_KEY='sx-...'
uvx llm 'fun facts about skunks'

This will install and run LLM using a temporary virtual environment.

You can use the --with option to add extra plugins. To use Anthropic's models, for example:

export ANTHROPIC_API_KEY='...'
uvx --with llm-anthropic llm -m claude-3.5-haiku 'fun facts about skunks'

All of the usual LLM commands will work with uvx llm​. Here's how to set your OpenAI key without needing an environment variable for example:

uvx llm keys set openai
# Paste key here

A note about Homebrew and PyTorch

The version of LLM packaged for Homebrew currently uses Python 3.12. The PyTorch project do not yet have a stable release of PyTorch for that version of Python.

This means that LLM plugins that depend on PyTorch such as llm-sentence-transformers <https://github.com/simonw/llm-sentence-transformers> may not install cleanly with the Homebrew version of LLM.

You can workaround this by manually installing PyTorch before installing llm-sentence-transformers:

llm install llm-python
llm python -m pip install \
  --pre torch torchvision \
  --index-url https://download.pytorch.org/whl/nightly/cpu
llm install llm-sentence-transformers

This should produce a working installation of that plugin.

Installing plugins

Plugins <#plugins> can be used to add support for other language models, including models that can run on your own device.

For example, the llm-gpt4all <https://github.com/simonw/llm-gpt4all> plugin adds support for 17 new models that can be installed on your own machine. You can install that like so:

llm install llm-gpt4all

API key management

Many LLM models require an API key. These API keys can be provided to this tool using several different mechanisms.

You can obtain an API key for OpenAI's language models from the API keys page <https://platform.openai.com/api-keys> on their site.

Saving and using stored keys

The easiest way to store an API key is to use the llm keys set command:

llm keys set openai

You will be prompted to enter the key like this:

% llm keys set openai
Enter key:

Once stored, this key will be automatically used for subsequent calls to the API:

llm "Five ludicrous names for a pet lobster"

You can list the names of keys that have been set using this command:

llm keys

Keys that are stored in this way live in a file called keys.json​. This file is located at the path shown when you run the following command:

llm keys path

On macOS this will be ~/Library/Application Support/io.datasette.llm/keys.json​. On Linux it may be something like ~/.config/io.datasette.llm/keys.json​.

Passing keys using the --key option

Keys can be passed directly using the --key option, like this:

llm "Five names for pet weasels" --key sk-my-key-goes-here

You can also pass the alias of a key stored in the keys.json file. For example, if you want to maintain a personal API key you could add that like this:

llm keys set personal

And then use it for prompts like so:

llm "Five friendly names for a pet skunk" --key personal

Keys in environment variables

Keys can also be set using an environment variable. These are different for different models.

For OpenAI models the key will be read from the OPENAI_API_KEY environment variable.

The environment variable will be used if no --key option is passed to the command and there is not a key configured in keys.json

To use an environment variable in place of the keys.json key run the prompt like this:

llm 'my prompt' --key $OPENAI_API_KEY

Configuration

You can configure LLM in a number of different ways.

Setting a custom default model

The model used when calling llm without the -m/--model option defaults to gpt-5.6-luna - a fast and less expensive OpenAI model.

You can use the llm models default command to set a different default model. For GPT-4o (slower and more expensive, but more capable) run this:

llm models default gpt-4o

You can view the current model by running this:

llm models default

Any of the supported aliases for a model can be passed to this command.

Setting a custom directory location

This tool stores various files - prompt templates, stored keys, preferences, a database of logs - in a directory on your computer.

On macOS this is ~/Library/Application Support/io.datasette.llm/​.

On Linux it may be something like ~/.config/io.datasette.llm/​.

You can set a custom location for this directory by setting the LLM_USER_PATH environment variable:

export LLM_USER_PATH=/path/to/my/custom/directory

Turning SQLite logging on and off

By default, LLM will log every prompt and response you make to a SQLite database - see Logging to SQLite <#logging> for more details.

You can turn this behavior off by default by running:

llm logs off

Or turn it back on again with:

llm logs on

Run llm logs status to see the current states of the setting.

Usage

The command to run a prompt is llm prompt 'your prompt'​. This is the default command, so you can use llm 'your prompt' as a shortcut.

Executing a prompt

These examples use the default OpenAI gpt-5.6-luna model, which requires you to first set an OpenAI API key <#api-keys>​.

You can install LLM plugins <#installing-plugins> to use models from other providers, including openly licensed models you can run directly on your own computer.

To run a prompt, streaming tokens as they come in:

llm 'Ten names for cheesecakes'

To disable streaming and only return the response once it has completed:

llm 'Ten names for cheesecakes' --no-stream

To switch from the default model to GPT-5.6 Sol:

llm 'Ten names for cheesecakes' -m gpt-5.6-sol

Pass --model <model name> to use a different model. Run llm models to see a list of available models.

Or if you know the name is too long to type, use -q once or more to provide search terms - the model with the shortest model ID that matches all of those terms (as a lowercase substring) will be used:

llm 'Ten names for cheesecakes' -q gpt -q sol

To change the default model for the current session, set the LLM_MODEL environment variable:

export LLM_MODEL=gpt-4.1
llm 'Ten names for cheesecakes' # Uses gpt-4.1

You can send a prompt directly to standard input like this:

echo 'Ten names for cheesecakes' | llm

If you send text to standard input and provide arguments, the resulting prompt will consist of the piped content followed by the arguments:

cat myscript.py | llm 'explain this code'

Will run a prompt of:

<contents of myscript.py> explain this code

For models that support them, system prompts are a better tool for this kind of prompting.

Model options

Some models support options. You can pass these using -o/--option name value - for example, to set the temperature to 1.5 run this:

llm 'Ten names for cheesecakes' -o temperature 1.5

Use the llm models --options command to see which options are supported by each model, or llm -m gpt-5.5 --options to show the options for a specific selected model.

You can also configure default options for a model using the llm models options commands.

Attachments

Some models are multi-modal, which means they can accept input in more than just text. GPT-4o and GPT-4o mini can accept images, and models such as Google's gemini-flash-latest can accept audio and video as well.

LLM calls these attachments​. You can pass attachments using the -a option like this:

llm "describe this image" -a https://static.simonwillison.net/static/2024/pelicans.jpg

Attachments can be passed using URLs or file paths, and you can attach more than one attachment to a single prompt:

llm "extract text" -a image1.jpg -a image2.jpg

You can also pipe an attachment to LLM by using - as the filename:

cat image.jpg | llm "describe this image" -a -

LLM will attempt to automatically detect the content type of the image. If this doesn't work you can instead use the --attachment-type option (--at for short) which takes the URL/path plus an explicit content type:

cat myfile | llm "describe this image" --at - image/jpeg

System prompts

You can use -s/--system '...' to set a system prompt.

llm 'SQL to calculate total sales by month' \
  --system 'You are an exaggerated sentient cheesecake that knows SQL and talks about cheesecake a lot'

This is useful for piping content to standard input, for example:

curl -s 'https://simonwillison.net/2023/May/15/per-interpreter-gils/' | \
  llm -s 'Suggest topics for this post as a JSON array'

Or to generate a description of changes made to a Git repository since the last commit:

git diff | llm -s 'Describe these changes'

Different models support system prompts in different ways.

The OpenAI models are particularly good at using system prompts as instructions for how they should process additional input sent as part of the regular prompt.

Other models might use system prompts change the default voice and attitude of the model.

System prompts can be saved as templates <#prompt-templates> to create reusable tools. For example, you can create a template called pytest like this:

llm -s 'write pytest tests for this code' --save pytest

And then use the new template like this:

cat llm/utils.py | llm -t pytest

See prompt templates <#prompt-templates> for more.

Tools

Many models support the ability to call external tools <#tools>​. Tools can be provided by plugins <#plugin-hooks-register-tools> or you can pass a --functions CODE option to LLM to define one or more Python functions that the model can then call.

llm --functions '
def multiply(x: int, y: int) -> int:
    """Multiply two numbers."""
    return x * y
' 'what is 34234 * 213345'

Add --td/--tools-debug to see full details of the tools that are being executed. You can also set the LLM_TOOLS_DEBUG environment variable to 1 to enable this for all prompts.

llm --functions '
def multiply(x: int, y: int) -> int:
    """Multiply two numbers."""
    return x * y
' 'what is 34234 * 213345' --td

Output:

Tool call: multiply({'x': 34234, 'y': 213345})
  7303652730
34234 multiplied by 213345 is 7,303,652,730.

Or add --ta/--tools-approve to approve each tool call interactively before it is executed:

llm --functions '
def multiply(x: int, y: int) -> int:
    """Multiply two numbers."""
    return x * y
' 'what is 34234 * 213345' --ta

Output:

Tool call: multiply({'x': 34234, 'y': 213345})
Approve tool call? [y/N]:

The --functions option can be passed more than once, and can also point to the filename of a ​.py file containing one or more functions.

If you have any tools that have been made available via plugins you can add them to the prompt using --tool/-T option. For example, using llm-tools-simpleeval <https://github.com/simonw/llm-tools-simpleeval> like this:

llm install llm-tools-simpleeval
llm --tool simple_eval "4444 * 233423" --td

Run this command to see a list of available tools from plugins:

llm tools

Server-side tools are model-specific. Pass -m/--model to include the tools supported by a particular model:

llm tools -m gpt-5.6-luna

These are displayed in a separate Server-side tools section with their constructor signatures and documentation. Add --json to return them in a server_side_tools array whose entries have "server_side": true​.

If you run a prompt that uses tools from plugins or model-specific server-side tools, continuing that conversation using llm -c will reuse the tools from the first prompt. Configured constructor arguments such as CodeInterpreter(memory_limit="4g") are retained. Running llm chat -c will start a chat that continues using those same tools. For example:

llm -T simple_eval "12345 * 12345" --td
Tool call: simple_eval({'expression': '12345 * 12345'})
  152399025
12345 multiplied by 12345 equals 152,399,025.
llm -c "that * 6" --td
Tool call: simple_eval({'expression': '152399025 * 6'})
  914394150
152,399,025 multiplied by 6 equals 914,394,150.
llm chat -c --td
Chatting with gpt-4.1-mini
Type 'exit' or 'quit' to exit
Type '!multi' to enter multiple lines, then '!end' to finish
Type '!edit' to open your default editor and modify the prompt
> / 123
Tool call: simple_eval({'expression': '914394150 / 123'})
  7434098.780487805
914,394,150 divided by 123 is approximately 7,434,098.78.

Some tools are bundled in a configurable collection of tools called a toolbox​. This means a single --tool option can load multiple related tools.

llm-tools-datasette <https://github.com/simonw/llm-tools-datasette> is one example. Using a toolbox looks like this:

llm install llm-tools-datasette
llm -T 'Datasette("https://datasette.io/content")' "Show tables" --td

Toolboxes always start with a capital letter. They can be configured by passing a tool specification, which should fit the following patterns:

  • Empty: ToolboxName or ToolboxName() - has no configuration arguments
  • JSON object: ToolboxName({"key": "value", "other": 42})
  • Single JSON value: ToolboxName("hello") or ToolboxName([1,2,3])
  • Key-value pairs: ToolboxName(name="test", count=5, items=[1,2]) - treated the same as {"name": "test", "count": 5, "items": [1, 2]}, all values must be valid JSON

The llm tools command lists toolboxes along with the tools they provide. Some toolboxes cannot know their list of tools until they have been configured - llm-mcp-client <https://github.com/simonw/llm-mcp-client> for example fetches its tools from whichever MCP server it is pointed at. These dynamic toolboxes are listed with their constructor signature and documentation instead:

MCP(server, mode='auto', prefix='') (plugin: mcp_client)

  Expose the tools from an MCP server as LLM tools.

  Usage:

      MCP("https://example.com/mcp")
      MCP("https://example.com/mcp", mode="legacy", prefix="demo_")

Pass a full toolbox specification to llm tools to see the tools provided by a configured instance:

llm tools 'MCP("https://datasette.simonwillison.net/-/mcp")'
MCP("https://datasette.simonwillison.net/-/mcp"):

  list_databases(**kwargs)

    List the databases available in this Datasette instance.

  get_database_schema(**kwargs)

    Return the complete SQL schema for a database.

  execute_sql(**kwargs)

    Execute one read-only SQL statement and return its tabular results.

Continuing a conversation with llm -c or llm chat -c reconstructs any toolboxes from the configuration recorded in the logs, so you don't need to repeat the -T option. Each instance is rebuilt fresh, which means any in-memory state a toolbox accumulated during the earlier prompt does not carry over.

Toolboxes work well with llm chat​. Try chatting with the Datasette content database like this:

llm chat -T 'Datasette("https://datasette.io/content")' --td
Chatting with gpt-4.1-mini
Type 'exit' or 'quit' to exit
​...
> show tables

Extracting fenced code blocks

If you are using an LLM to generate code it can be useful to retrieve just the code it produces without any of the surrounding explanatory text.

The -x/--extract option will scan the response for the first instance of a Markdown fenced code block - something that looks like this:

```python
def my_function():
    # ...
```

It will extract and returns just the content of that block, excluding the fenced coded delimiters. If there are no fenced code blocks it will return the full response.

Use --xl/--extract-last to return the last fenced code block instead of the first.

The entire response including explanatory text is still logged to the database, and can be viewed using llm logs -c​.

JSON output

Add --json to get back a JSON array describing the prompt and the response, in the same format as llm logs --json <#logging-view>:

llm 'Five names for a pet pelican' --json
[
  {
    "id": "01jm8ec74wxsdatyn5pq1fp0s5",
    "model": "gpt-5.6-luna",
    "resolved_model": null,
    "prompt": "Five names for a pet pelican",
    "system": null,
    "prompt_json": null,
    "options_json": {},
    "response": "1. Captain Beaky\n...",
    "reasoning": null,
    "response_json": null,
    "conversation_id": "01jm8ec74taftdgj2t4zra9z0j",
    "duration_ms": 1560,
    "datetime_utc": "2025-02-16T22:34:30.374882+00:00",
    "input_tokens": 8,
    "output_tokens": 62,
    "token_details": null,
    "conversation_name": "Five names for a pet pelican",
    "conversation_model": "gpt-5.6-luna",
    "schema_json": null,
    "prompt_fragments": [],
    "system_fragments": [],
    "tools": [],
    "tool_calls": [],
    "tool_results": [],
    "attachments": []
  }
]

The array will contain more than one object if the prompt triggered tool calls, since each round-trip with the model is logged as a separate response.

This works even if logging is turned off or you use -n/--no-log - in that case the JSON is assembled without writing anything to your logs database.

Schemas

Some models include the ability to return JSON that matches a provided JSON schema <https://json-schema.org/>​. Models from OpenAI, Anthropic and Google Gemini all include this capability.

Take a look at the schemas documentation <#schemas> for a detailed guide to using this feature.

You can pass JSON schemas directly to the --schema option:

llm --schema '{
  "type": "object",
  "properties": {
    "dogs": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "name": {
            "type": "string"
          },
          "bio": {
            "type": "string"
          }
        }
      }
    }
  }
}' -m gpt-5.6-sol 'invent two dogs'

Or use LLM's custom concise schema syntax <#schemas-dsl> like this:

llm --schema 'name,bio' 'invent a dog'

Two use the same concise schema for multiple items use --schema-multi:

llm --schema-multi 'name,bio' 'invent two dogs'

You can also save the JSON schema to a file and reference the filename using --schema:

llm --schema dogs.schema.json 'invent two dogs'

Or save your schema to a template <#prompt-templates> like this:

llm --schema dogs.schema.json --save dogs
# Then to use it:
llm -t dogs 'invent two dogs'

Be warned that different models may support different dialects of the JSON schema specification.

See Browsing logged JSON objects created using schemas <#schemas-logs> for tips on using the llm logs --schema X command to access JSON objects you have previously logged using this option.

Fragments

You can use the -f/--fragment option to reference fragments of context that you would like to load into your prompt. Fragments can be specified as URLs, file paths or as aliases to previously saved fragments.

Fragments are designed for running longer prompts. LLM stores prompts in a database <#logging>, and the same prompt repeated many times can end up stored as multiple copies, wasting disk space. A fragment will be stored just once and referenced by all of the prompts that use it.

The -f option can accept a path to a file on disk, a URL or the hash or alias of a previous fragment.

For example, to ask a question about the robots.txt file on llm.datasette.io:

llm -f https://llm.datasette.io/robots.txt 'explain this'

For a poem inspired by some Python code on disk:

llm -f cli.py 'a short snappy poem inspired by this code'

You can use as many -f options as you like - the fragments will be concatenated together in the order you provided, with any additional prompt added at the end.

Fragments can also be used for the system prompt using the --sf/--system-fragment option. If you have a file called explain_code.txt containing this:

Explain this code in detail. Include copies of the code quoted in the explanation.

You can run it as the system prompt like this:

llm -f cli.py --sf explain_code.txt

You can use the llm fragments set command to load a fragment and give it an alias for use in future queries:

llm fragments set cli cli.py
# Then
llm -f cli 'explain this code'

Use llm fragments to list all fragments that have been stored:

llm fragments

You can search by passing one or more -q X search strings. This will return results matching all of those strings, across the source, hash, aliases and content:

llm fragments -q pytest -q asyncio

The llm fragments remove command removes an alias. It does not delete the fragment record itself as those are linked to previous prompts and responses and cannot be deleted independently of them.

llm fragments remove cli

Continuing a conversation

By default, the tool will start a new conversation each time you run it.

You can opt to continue the previous conversation by passing the -c/--continue option:

llm 'More names' -c

This will re-send the prompts and responses for the previous conversation as part of the call to the language model. Note that this can add up quickly in terms of tokens, especially if you are using expensive models.

--continue will automatically use the same model as the conversation that you are continuing, even if you omit the -m/--model option.

To continue a conversation that is not the most recent one, use the --cid/--conversation <id> option:

llm 'More names' --cid 01h53zma5txeby33t1kbe3xk8q

You can find these conversation IDs using the llm logs command.

Tips for using LLM with Bash or Zsh

To learn more about your computer's operating system based on the output of uname -a, run this:

llm "Tell me about my operating system: $(uname -a)"

This pattern of using $(command) inside a double quoted string is a useful way to quickly assemble prompts.

Completion prompts

Some models are completion models - rather than being tuned to respond to chat style prompts, they are designed to complete a sentence or paragraph.

An example of this is the gpt-3.5-turbo-instruct OpenAI model.

You can prompt that model the same way as the chat models, but be aware that the prompt format that works best is likely to differ.

llm -m gpt-3.5-turbo-instruct 'Reasons to tame a wild beaver:'

Starting an interactive chat

The llm chat command starts an ongoing interactive chat with a model.

This is particularly useful for models that run on your own machine, since it saves them from having to be loaded into memory each time a new prompt is added to a conversation.

Run llm chat, optionally with a -m model_id, to start a chat conversation:

llm chat -m chatgpt

Each chat starts a new conversation. A record of each conversation can be accessed through the logs <#logging-conversation>​.

You can pass -c to start a conversation as a continuation of your most recent prompt. This will automatically use the most recently used model:

llm chat -c

For models that support them, you can pass options using -o/--option:

llm chat -m gpt-4.1 -o temperature 0.5

You can pass a system prompt to be used for your chat conversation:

llm chat -m gpt-5.6-luna -s 'You are a sentient cheesecake'

You can also pass a template <#prompt-templates> - useful for creating chat personas that you wish to return to.

Here's how to create a template for your GPT-5.6 Luna powered cheesecake:

llm --system 'You are a sentient cheesecake' -m gpt-5.6-luna --save cheesecake

Now you can start a new chat with your cheesecake any time you like using this:

llm chat -t cheesecake
Chatting with gpt-5.6-luna
Type 'exit' or 'quit' to exit
Type '!multi' to enter multiple lines, then '!end' to finish
Type '!edit' to open your default editor and modify the prompt
Type '!fragment <my_fragment> [<another_fragment> ...]' to insert one or more fragments
> who are you?
I am a sentient cheesecake, meaning I am an artificial
intelligence embodied in a dessert form, specifically a
cheesecake. However, I don't consume or prepare foods
like humans do, I communicate, learn and help answer
your queries.

Type quit or exit followed by <enter> to end a chat session.

Sometimes you may want to paste multiple lines of text into a chat at once - for example when debugging an error message.

To do that, type !multi to start a multi-line input. Type or paste your text, then type !end and hit <enter> to finish.

If your pasted text might itself contain a !end line, you can set a custom delimiter using !multi abc followed by !end abc at the end:

Chatting with gpt-5.6-luna
Type 'exit' or 'quit' to exit
Type '!multi' to enter multiple lines, then '!end' to finish
Type '!edit' to open your default editor and modify the prompt.
Type '!fragment <my_fragment> [<another_fragment> ...]' to insert one or more fragments
> !multi custom-end
 Explain this error:

   File "/opt/homebrew/Caskroom/miniconda/base/lib/python3.10/urllib/request.py", line 1391, in https_open
    return self.do_open(http.client.HTTPSConnection, req,
  File "/opt/homebrew/Caskroom/miniconda/base/lib/python3.10/urllib/request.py", line 1351, in do_open
    raise URLError(err)
urllib.error.URLError: <urlopen error [Errno 8] nodename nor servname provided, or not known>

 !end custom-end

You can also use !edit to open your default editor and modify the prompt before sending it to the model.

Chatting with gpt-5.6-luna
Type 'exit' or 'quit' to exit
Type '!multi' to enter multiple lines, then '!end' to finish
Type '!edit' to open your default editor and modify the prompt.
Type '!fragment <my_fragment> [<another_fragment> ...]' to insert one or more fragments
> !edit

llm chat takes the same --tool/-T and --functions options as llm prompt​. You can use this to start a chat with the specified tools enabled.

Listing available models

The llm models command lists every model that can be used with LLM, along with their aliases. This includes models that have been installed using plugins <#plugins>​.

llm models

Example output:

OpenAI Responses: gpt-5.5
OpenAI Responses: gpt-5.5-2026-04-23
OpenAI Responses: gpt-5.6-sol
OpenAI Responses: gpt-5.6-terra
OpenAI Responses: gpt-5.6-luna (aliases: luna)
​...

Add one or more -q term options to search for models matching all of those search terms:

llm models -q gpt-5.6
llm models -q gpt -q sol

Use one or more -m options to indicate specific models, either by their model ID or one of their aliases:

llm models -m gpt-5.6-luna -m claude-opus-4.8

Add --json to return an array of model records with aliases, capability flags, attachment types and server_side_tools​. Combine it with -m to inspect one or more specific models; adding --options includes each model's option schemas:

llm models --json -m gpt-5.6-luna

Add --options to also see documentation for the options supported by each model:

llm models --options

Output:

OpenAI Chat: gpt-4o (aliases: 4o)
  Options:
    temperature: float
      What sampling temperature to use, between 0 and 2. Higher values like
      0.8 will make the output more random, while lower values like 0.2 will
      make it more focused and deterministic.
    max_tokens: int
      Maximum number of tokens to generate.
    top_p: float
      An alternative to sampling with temperature, called nucleus sampling,
      where the model considers the results of the tokens with top_p
      probability mass. So 0.1 means only the tokens comprising the top 10%
      probability mass are considered. Recommended to use top_p or
      temperature but not both.
    frequency_penalty: float
      Number between -2.0 and 2.0. Positive values penalize new tokens based
      on their existing frequency in the text so far, decreasing the model's
      likelihood to repeat the same line verbatim.
    presence_penalty: float
      Number between -2.0 and 2.0. Positive values penalize new tokens based
      on whether they appear in the text so far, increasing the model's
      likelihood to talk about new topics.
    stop: str
      A string where the API will stop generating further tokens.
    logit_bias: dict, str
      Modify the likelihood of specified tokens appearing in the completion.
      Pass a JSON string like '{"1712":-100, "892":-100, "1489":-100}'
    seed: int
      Integer seed to attempt to sample deterministically
    json_object: boolean
      Output a valid JSON object {...}. Prompt must mention JSON.
    image_detail: str
      Controls the detail level for image attachments. Supported values are
      low, high, and auto.
    service_tier: str
      The processing tier to use for this request - for example 'fast' for
      Fast mode (faster responses at a higher price) or 'flex' for slower,
      cheaper processing on models that support those tiers.
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Chat: gpt-4o-mini (aliases: 4o-mini)
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    image_detail: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Chat: gpt-4.1 (aliases: 4.1)
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    image_detail: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Chat: gpt-4.1-mini (aliases: 4.1-mini)
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    image_detail: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Chat: gpt-4.1-nano (aliases: 4.1-nano)
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    image_detail: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Chat: gpt-3.5-turbo (aliases: 3.5, chatgpt)
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    image_detail: str
    service_tier: str
  Features:
  - streaming
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Chat: gpt-3.5-turbo-16k (aliases: chatgpt-16k, 3.5-16k)
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    image_detail: str
    service_tier: str
  Features:
  - streaming
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Chat: gpt-4 (aliases: 4, gpt4)
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    image_detail: str
    service_tier: str
  Features:
  - streaming
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Chat: gpt-4-turbo-2024-04-09
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    image_detail: str
    service_tier: str
  Features:
  - streaming
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Chat: gpt-4-turbo (aliases: gpt-4-turbo-preview, 4-turbo, 4t)
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    image_detail: str
    service_tier: str
  Features:
  - streaming
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: o1
  Options:
    temperature: float
      What sampling temperature to use, between 0 and 2. Higher values like
      0.8 will make the output more random, while lower values like 0.2 will
      make it more focused and deterministic.
    max_tokens: int
      Maximum number of tokens to generate.
    top_p: float
      An alternative to sampling with temperature, called nucleus sampling,
      where the model considers the results of the tokens with top_p
      probability mass. So 0.1 means only the tokens comprising the top 10%
      probability mass are considered. Recommended to use top_p or
      temperature but not both.
    frequency_penalty: float
      Number between -2.0 and 2.0. Positive values penalize new tokens based
      on their existing frequency in the text so far, decreasing the model's
      likelihood to repeat the same line verbatim.
    presence_penalty: float
      Number between -2.0 and 2.0. Positive values penalize new tokens based
      on whether they appear in the text so far, increasing the model's
      likelihood to talk about new topics.
    stop: str
      A string where the API will stop generating further tokens.
    logit_bias: dict, str
      Modify the likelihood of specified tokens appearing in the completion.
      Pass a JSON string like '{"1712":-100, "892":-100, "1489":-100}'
    seed: int
      Integer seed to attempt to sample deterministically
    json_object: boolean
      Output a valid JSON object {...}. Prompt must mention JSON.
    chat_completions: boolean
      Force the use of the older /v1/chat/completions endpoint instead of
      /v1/responses. Most callers should leave this off; set to true to fall
      back to the Chat Completions code path for compatibility.
    image_detail: str
      Controls the detail level for image attachments. Supported values are
      low, high, and auto.
    reasoning_effort: str
      Constraints effort on reasoning for reasoning models. Currently
      supported values are low, medium, and high. Reducing reasoning effort
      can result in faster responses and fewer tokens used on reasoning in a
      response.
    reasoning_summary: str
      Requests a summary of the model's reasoning. Supported values are
      auto, concise, and detailed.
    service_tier: str
      The processing tier to use for this request - for example 'fast' for
      Fast mode (faster responses at a higher price) or 'flex' for slower,
      cheaper processing on models that support those tiers.
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: o1-2024-12-17
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: o3-mini
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    service_tier: str
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: o3
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: o4-mini
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5-mini
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5-nano
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5-2025-08-07
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5-mini-2025-08-07
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5-nano-2025-08-07
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.1
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.2
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.2-chat-latest
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.4
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.4-2026-03-05
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.4-mini
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.4-mini-2026-03-17
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.4-nano
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.4-nano-2026-03-17
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.5
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.5-2026-04-23
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.6-sol
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.6-terra
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Responses: gpt-5.6-luna
  Options:
    temperature: float
    max_tokens: int
    top_p: float
    frequency_penalty: float
    presence_penalty: float
    stop: str
    logit_bias: dict, str
    seed: int
    json_object: boolean
    chat_completions: boolean
    image_detail: str
    reasoning_effort: str
    reasoning_summary: str
    verbosity: str
    service_tier: str
  Attachment types:
    application/pdf, image/gif, image/jpeg, image/png, image/webp
  Features:
  - streaming
  - schemas
  - tools
  - async
  Keys:
    key: openai
    env_var: OPENAI_API_KEY
OpenAI Completion: gpt-3.5-turbo-instruct (aliases: 3.5-instruct, chatgpt-instruct)
  Options:
    temperature: float
      What sampling temperature to use, between 0 and 2. Higher values like
      0.8 will make the output more random, while lower values like 0.2 will
      make it more focused and deterministic.
    max_tokens: int
      Maximum number of tokens to generate.
    top_p: float
      An alternative to sampling with temperature, called nucleus sampling,
      where the model considers the results of the tokens with top_p
      probability mass. So 0.1 means only the tokens comprising the top 10%
      probability mass are considered. Recommended to use top_p or
      temperature but not both.
    frequency_penalty: float
      Number between -2.0 and 2.0. Positive values penalize new tokens based
      on their existing frequency in the text so far, decreasing the model's
      likelihood to repeat the same line verbatim.
    presence_penalty: float
      Number between -2.0 and 2.0. Positive values penalize new tokens based
      on whether they appear in the text so far, increasing the model's
      likelihood to talk about new topics.
    stop: str
      A string where the API will stop generating further tokens.
    logit_bias: dict, str
      Modify the likelihood of specified tokens appearing in the completion.
      Pass a JSON string like '{"1712":-100, "892":-100, "1489":-100}'
    seed: int
      Integer seed to attempt to sample deterministically
    logprobs: int
      Include the log probabilities of most likely N per token
  Features:
  - streaming
  Keys:
    key: openai
    env_var: OPENAI_API_KEY

When running a prompt you can pass the full model name or any of the aliases to the -m/--model option:

llm -m luna \
  'As many names for cheesecakes as you can think of, with detailed descriptions'

Setting default options for models

To configure a default option for a specific model, use the llm models options set command:

llm models options set gpt-4.1 temperature 0.5

This option will then be applied automatically any time you run a prompt through the gpt-4o model.

Default options are stored in the model_options.json file in the LLM configuration directory.

You can list all default options across all models using the llm models options list command:

llm models options list

Or show them for an individual model with llm models options show <model_id>:

llm models options show gpt-4.1

To clear a default option, use the llm models options clear command:

llm models options clear gpt-4.1 temperature

Or clear all default options for a model like this:

llm models options clear gpt-4.1

Default model options are respected by both the llm prompt and the llm chat commands. They will not be applied when you use LLM as a Python library <#python-api>​.

OpenAI models

LLM ships with a default plugin for talking to OpenAI's API. OpenAI offer both language models and embedding models, and LLM can access both types.

Configuration

All OpenAI models are accessed using an API key. You can obtain one from the API keys page <https://platform.openai.com/api-keys> on their site.

Once you have created a key, configure LLM to use it by running:

llm keys set openai

Then paste in the API key.

OpenAI language models

Run llm models for a full list of available models. The OpenAI models supported by LLM are:

OpenAI Chat: gpt-4o (aliases: 4o)
OpenAI Chat: gpt-4o-mini (aliases: 4o-mini)
OpenAI Chat: gpt-4.1 (aliases: 4.1)
OpenAI Chat: gpt-4.1-mini (aliases: 4.1-mini)
OpenAI Chat: gpt-4.1-nano (aliases: 4.1-nano)
OpenAI Chat: gpt-3.5-turbo (aliases: 3.5, chatgpt)
OpenAI Chat: gpt-3.5-turbo-16k (aliases: chatgpt-16k, 3.5-16k)
OpenAI Chat: gpt-4 (aliases: 4, gpt4)
OpenAI Chat: gpt-4-turbo-2024-04-09
OpenAI Chat: gpt-4-turbo (aliases: gpt-4-turbo-preview, 4-turbo, 4t)
OpenAI Responses: o1
OpenAI Responses: o1-2024-12-17
OpenAI Responses: o3-mini
OpenAI Responses: o3
OpenAI Responses: o4-mini
OpenAI Responses: gpt-5
OpenAI Responses: gpt-5-mini
OpenAI Responses: gpt-5-nano
OpenAI Responses: gpt-5-2025-08-07
OpenAI Responses: gpt-5-mini-2025-08-07
OpenAI Responses: gpt-5-nano-2025-08-07
OpenAI Responses: gpt-5.1
OpenAI Responses: gpt-5.2
OpenAI Responses: gpt-5.2-chat-latest
OpenAI Responses: gpt-5.4
OpenAI Responses: gpt-5.4-2026-03-05
OpenAI Responses: gpt-5.4-mini
OpenAI Responses: gpt-5.4-mini-2026-03-17
OpenAI Responses: gpt-5.4-nano
OpenAI Responses: gpt-5.4-nano-2026-03-17
OpenAI Responses: gpt-5.5
OpenAI Responses: gpt-5.5-2026-04-23
OpenAI Responses: gpt-5.6-sol
OpenAI Responses: gpt-5.6-terra
OpenAI Responses: gpt-5.6-luna
OpenAI Completion: gpt-3.5-turbo-instruct (aliases: 3.5-instruct, chatgpt-instruct)

See the OpenAI models documentation <https://platform.openai.com/docs/models> for details of each of these.

gpt-5.6-luna is one of the less expensive models, and is the default for if you don't specify a model at all. Consult OpenAI's model documentation <https://platform.openai.com/docs/models> for details of the other models.

Model features

The following features work with OpenAI models:

  • System prompts <#usage-system-prompts> can be used to provide instructions that have a higher weight than the prompt itself.
  • Attachments <#usage-attachments>​. Many OpenAI models support image inputs - check which ones using llm models --options​. Any model that accepts images can also accept PDFs.
  • Schemas <#usage-schemas> can be used to influence the JSON structure of the model output.
  • Model options <#usage-model-options> can be used to set parameters like temperature​. Use llm models --options for a full list of supported options.

Code Interpreter

Models that use the OpenAI Responses API can run Python in an OpenAI-managed container using the CodeInterpreter server-side tool:

llm -m gpt-5.6-luna -T 'CodeInterpreter(memory_limit="4g")' 'Run this calculation'

The same tool can be used from Python:

import llm
from llm.default_plugins.openai_models import CodeInterpreter

model = llm.get_model("gpt-5.6-luna")
response = model.prompt(
    "Use the python tool to calculate 111111 * 333333",
    tools=[CodeInterpreter()],
)
print(response.text())

OpenAI calls this Code Interpreter, but models know it as the "python tool", so referring to that name in the prompt is the most explicit way to request it.

By default OpenAI automatically creates a 1 GB container, or reuses an active container from the model's context. Configure a larger automatic container or make existing OpenAI files available to it like this:

CodeInterpreter(
    memory_limit="4g",
    file_ids=["file-1", "file-2"],
)

The accepted memory limits are 1g, 4g, 16g and 64g​. Higher limits cost more. To reuse a container that was created separately, pass its ID:

CodeInterpreter(container="cntr_abc123")

An explicit container ID cannot be combined with memory_limit or file_ids​. LLM automatically requests the full Code Interpreter output and records returned code and output as server-executed tool parts; it never tries to run that code locally.

OpenAI containers are ephemeral and expire after 20 minutes without activity. See OpenAI's Code Interpreter documentation <https://developers.openai.com/api/docs/guides/tools-code-interpreter> for container behavior, supported files and current pricing details.

Fast mode and service tiers

OpenAI models can process requests at different speeds and prices using the service_tier API parameter. Fast mode <https://developers.openai.com/api/docs/guides/fast-mode> runs up to 2.5x faster than standard processing at a higher per-token price, with the biggest speed increase on gpt-5.6-sol​. Flex processing <https://developers.openai.com/api/docs/guides/flex-processing> is slower but cheaper. Each tier works with a different subset of models - the Fast and Flex tables on OpenAI's pricing page <https://developers.openai.com/api/docs/pricing> are the definitive list of which models support which tier.

All of the OpenAI models supported by LLM expose a service_tier option, with the exception of the legacy gpt-3.5-turbo-instruct completion model. Use -o service_tier fast to enable Fast mode for a prompt:

llm -m gpt-5.6-sol -o service_tier fast 'Fast facts about pelicans'

The value is passed straight to the API, so other tiers such as priority (the older name for fast) and flex (slower but cheaper processing <https://developers.openai.com/api/docs/guides/flex-processing>) work too:

llm -m gpt-5.4 -o service_tier flex 'No rush: facts about pelicans'

OpenAI embedding models

Run llm embed-models for a list of embedding models <#embeddings>​. The following OpenAI embedding models are supported by LLM:

ada-002 (aliases: ada, oai)
3-small
3-large
3-small-512
3-large-256
3-large-1024

The 3-small model is currently the most inexpensive. 3-large costs more but is more capable - see New embedding models and API updates <https://openai.com/blog/new-embedding-models-and-api-updates> on the OpenAI blog for details and benchmarks.

An important characteristic of any embedding model is the size of the vector it returns. Smaller vectors cost less to store and query, but may be less accurate.

OpenAI 3-small and 3-large vectors can be safely truncated to lower dimensions without losing too much accuracy. The -int models provided by LLM are pre-configured to do this, so 3-large-256 is the 3-large model truncated to 256 dimensions.

The vector size of the supported OpenAI embedding models are as follows:

ModelSize
ada-0021536
3-small1536
3-large3072
3-small-512512
3-large-256256
3-large-10241024

OpenAI completion models

The gpt-3.5-turbo-instruct model is a little different - it is a completion model rather than a chat model, described in the OpenAI completions documentation <https://platform.openai.com/docs/api-reference/completions/create>​.

Adding more OpenAI models

OpenAI occasionally release new models with new names. LLM aims to ship new releases to support these, but you can also configure them directly, by adding them to a extra-openai-models.yaml configuration file.

Run this command to find the directory in which this file should be created:

dirname "$(llm logs path)"

On my Mac laptop I get this:

~/Library/Application Support/io.datasette.llm

Create a file in that directory called extra-openai-models.yaml​.

Let's say OpenAI have just released the gpt-3.5-turbo-0613 model and you want to use it, despite LLM not yet shipping support. You could configure that by adding this to the file:

- model_id: gpt-3.5-turbo-0613
  model_name: gpt-3.5-turbo-0613
  aliases: ["0613"]

The model_id is the identifier that will be recorded in the LLM logs. You can use this to specify the model, or you can optionally include a list of aliases for that model. The model_name is the actual model identifier that will be passed to the API, which must match exactly what the API expects.

If the model is a completion model (such as gpt-3.5-turbo-instruct) add completion: true to the configuration.

If the model should use the OpenAI Responses API rather than Chat Completions, add responses: true to the configuration. This is useful for models such as o1, o3-mini and gpt-5-style models that are accessed through /v1/responses​.

If the model supports structured extraction using json_schema, add supports_schema: true to the configuration.

For reasoning models like o1 or o3-mini add reasoning: true​.

If the model supports the service_tier parameter - see Fast mode and service tiers - add service_tier: true to enable the corresponding option.

With this configuration in place, the following command should run a prompt against the new model:

llm -m 0613 'What is the capital of France?'

Run llm models to confirm that the new model is now available:

llm models

Example output:

OpenAI Chat: gpt-3.5-turbo (aliases: 3.5, chatgpt)
OpenAI Chat: gpt-3.5-turbo-16k (aliases: chatgpt-16k, 3.5-16k)
OpenAI Chat: gpt-4 (aliases: 4, gpt4)
OpenAI Chat: gpt-3.5-turbo-0613 (aliases: 0613)

Running llm logs -n 1 should confirm that the prompt and response has been correctly logged to the database.

Other models

LLM supports OpenAI models by default. You can install plugins <#plugins> to add support for other models. You can also add additional OpenAI-API-compatible models using a configuration file <#openai-extra-models>​.

Installing and using a local model

LLM plugins <#plugins> can provide local models that run on your machine.

To install llm-gpt4all <https://github.com/simonw/llm-gpt4all>, providing 17 models from the GPT4All <https://gpt4all.io/> project, run this:

llm install llm-gpt4all

Run llm models to see the expanded list of available models.

To run a prompt through one of the models from GPT4All specify it using -m/--model:

llm -m orca-mini-3b-gguf2-q4_0 'What is the capital of France?'

The model will be downloaded and cached the first time you use it.

Check the plugin directory <#plugin-directory> for the latest list of available plugins for other models.

OpenAI-compatible models

Projects such as LocalAI <https://localai.io/> offer a REST API that imitates the OpenAI API but can be used to run other models, including models that can be installed on your own machine. These can be added using the same configuration mechanism.

Run against an endpoint without configuring it

Use llm openai endpoint to run a prompt directly against an OpenAI-compatible base URL:

llm openai endpoint https://example.com/v1 \
  -m model-id \
  "What is the capital of France?"

This command does not register the model and does not log the prompt or response. It also does not send your configured OpenAI API key to the endpoint. Use --key to explicitly provide a key or the alias of a key saved using llm keys set:

llm openai endpoint https://example.com/v1 \
  -m model-id \
  --key custom-endpoint \
  "What is the capital of France?"

List the model IDs advertised by the endpoint using --models​. This requests the models resource relative to the base URL, so a base URL ending in /v1 will request /v1/models:

llm openai endpoint https://example.com/v1 --models

Omit the prompt to read it from stdin. In an interactive terminal the command waits for input until EOF, matching llm prompt:

llm openai endpoint https://example.com/v1 -m model-id

Use --chat to start an interactive chat:

llm openai endpoint https://example.com/v1 -m model-id --chat

Use -a or --attachment to attach an image or PDF. Chat Completions endpoints can also receive WAV or MP3 audio attachments:

llm openai endpoint https://example.com/v1 \
  -m model-id \
  -a image.jpg \
  "Describe this image"

Use --at path-or-url mimetype when the attachment type cannot be inferred. Attachments provided when starting an interactive chat are included with the first message.

Use -t or --template to apply an existing LLM template. Template prompts, system prompts, defaults, model options, model IDs, schemas, and attachments are supported. Pass template variables using -p or --param:

llm openai endpoint https://example.com/v1 \
  -t summarize \
  -p style concise \
  "Text to summarize"

The -m option can be omitted if the template specifies a model. In an interactive chat started using --chat, the template is applied to each turn. Without --chat, a template that provides its own prompt runs once even when no prompt argument is supplied.

Use --schema to request structured JSON output or --schema-multi to request an array of matching items. These accept the same inline JSON, file paths, stored schema IDs, template references and concise schema syntax <#schemas-dsl> as llm prompt:

llm openai endpoint https://example.com/v1 \
  -m model-id \
  --schema 'name, age int' \
  "Invent a dog"

Reasoning-capable endpoints can be given a reasoning effort using -o reasoning_effort, with a value of none, minimal, low, medium, high, xhigh, or max:

llm openai endpoint https://example.com/v1 \
  -m model-id \
  -o reasoning_effort high \
  "Solve this problem"

Responses API endpoints can also be asked for a visible reasoning summary using -o reasoning_summary, with a value of auto, concise, or detailed:

llm openai endpoint https://example.com/v1 \
  --responses \
  -m model-id \
  -o reasoning_summary auto \
  "Solve this problem"

This maps to the Responses API reasoning.summary request field. auto asks the endpoint for the most detailed summary available for that model. Use -R or --hide-reasoning to suppress summary generation for a request.

The command does not send reasoning-specific request fields by default and does not request a reasoning summary unless one of these options is used. An endpoint that does not support an option will return its own API error.

Use -T or --tool to make an installed LLM tool available to the model, or --functions to load Python functions from an inline code block or file:

llm openai endpoint https://example.com/v1 \
  -m model-id \
  -T llm_time \
  --functions tools.py \
  "What time is it?"

Tool calls are executed locally and their results are sent back to the endpoint until it returns a final answer. --chain-limit controls the maximum number of responses, --tools-debug shows tool execution details, and --tools-approve asks for confirmation before each call. Tools and trusted Python functions declared by local templates are supported too.

The command uses the Chat Completions API by default. Add --responses for an endpoint that implements the Responses API:

llm openai endpoint https://example.com/v1 \
  -m model-id \
  --responses \
  "What is the capital of France?"

Responses endpoints can define their own server-side tool types. Use ServerSideTool to pass an endpoint-specific tool specification through without validation. For example, OpenRouter's web search server tool <https://openrouter.ai/docs/api/reference/responses/web-search> can be used like this:

llm openai endpoint https://openrouter.ai/api/v1 \
  -m openai/gpt-oss-20b:free \
  --key openrouter \
  --responses \
  -R \
  -T 'ServerSideTool(spec={"type":"openrouter:web_search","parameters":{"engine":"exa","max_results":2,"max_uses":1}})' \
  "Search for the OpenRouter documentation URL"

-R hides the reasoning text returned by this model so the command displays just its final answer.

Configure an OpenAI-compatible model

The model_id is the name LLM will use for the model. The model_name is the name which needs to be passed to the API - this might differ from the model_id, especially if the model_id could potentially clash with other installed models.

The api_base key can be used to point the OpenAI client library at a different API endpoint.

To add the orca-mini-3b model hosted by a local installation of LocalAI <https://localai.io/>, add this to your extra-openai-models.yaml file:

- model_id: orca-openai-compat
  model_name: orca-mini-3b.ggmlv3
  api_base: "http://localhost:8080"

If the api_base is set, the existing configured openai API key will not be sent by default.

You can set api_key_name to the name of a key stored using the API key management <#api-keys> feature.

Other keys you can use here:

  • completion: true for completion models that should use the /completion endpoint as opposed to /completion/chat
  • responses: true for models that should use the OpenAI Responses API (/responses) instead of the Chat Completions API (/chat/completions)
  • supports_tools: true for models that support tool calling
  • can_stream: false to disable streaming mode for models that cannot stream
  • supports_schema: true for models that support JSON structured schema output
  • vision: true for models that can accept images as input
  • audio: true for models that accept audio attachments

Having configured the model like this, run llm models --options -m MODEL_ID to check that it installed correctly. You can then run prompts against it like so:

llm -m orca-openai-compat 'What is the capital of France?'

And confirm they were logged correctly with:

llm logs -n 1

Extra HTTP headers

Some providers such as openrouter.ai <https://openrouter.ai/docs> may require the setting of additional HTTP headers. You can set those using the headers: key like this:

- model_id: claude
  model_name: anthropic/claude-2
  api_base: "https://openrouter.ai/api/v1"
  api_key_name: openrouter
  headers:
    HTTP-Referer: "https://llm.datasette.io/"
    X-Title: LLM

Tools

Many Large Language Models have been trained to execute tools as part of responding to a prompt. LLM supports tool usage with both the command-line interface and the Python API.

Exposing tools to LLMs carries risks! Be sure to read the warning below​.

How tools work

A tool is effectively a function that the model can request to be executed. Here's how that works:

  1. The initial prompt to the model includes a list of available tools, containing their names, descriptions and parameters.
  2. The model can choose to call one (or sometimes more than one) of those tools, returning a request for the tool to execute.
  3. The code that calls the model - in this case LLM itself - then executes the specified tool with the provided arguments.
  4. LLM prompts the model a second time, this time including the output of the tool execution.
  5. The model can then use that output to generate its next response.

This sequence can run several times in a loop, allowing the LLM to access data, act on that data and then pass that data off to other tools for further processing.

Tools can be dangerous

Warning: Tools can be dangerous

Applications built on top of LLMs suffer from a class of attacks called prompt injection <https://simonwillison.net/tags/prompt-injection/> attacks. These occur when a malicious third party injects content into the LLM which causes it to take tool-based actions that act against the interests of the user of that application.

Be very careful about which tools you enable when you potentially might be exposed to untrusted sources of content - web pages, GitHub issues posted by other people, email and messages that have been sent to you that could come from an attacker.

Watch out for the lethal trifecta <https://simonwillison.net/2025/Jun/16/the-lethal-trifecta/> of prompt injection exfiltration attacks. If your tool-enabled LLM has the following:

  • access to private data
  • exposure to malicious instructions
  • the ability to exfiltrate information

Anyone who can feed malicious instructions into your LLM - by leaving them on a web page it visits, or sending an email to an inbox that it monitors - could be able to trick your LLM into using other tools to access your private information and then exfiltrate (pass out) that data to somewhere the attacker can see it.

Trying out tools

LLM comes with a default tool installed, called llm_version​. You can try that out like this:

llm --tool llm_version "What version of LLM is this?" --td

You can also use -T llm_version as a shortcut for --tool llm_version​.

The output should look like this:

Tool call: llm_version({})
  0.26a0

The installed version of the LLM is 0.26a0.

Further tools can be installed using plugins, or you can use the llm --functions option to pass tools implemented as PYthon functions directly, as described here <#usage-tools>​.

LLM's implementation of tools

In LLM every tool is defined as a Python function. The function can take any number of arguments and can return a string or an object that can be converted to a string.

Tool functions should include a docstring that describes what the function does. This docstring will become the description that is passed to the model.

Tools can also be defined as toolbox classes <#python-api-toolbox>, a subclass of llm.Toolbox that allows multiple related tools to be bundled together. Toolbox classes can be configured when they are instantiated, and can also maintain state in between multiple tool calls.

The Python API can accept functions directly. The command-line interface has two ways for tools to be defined: via plugins that implement the register_tools() plugin hook <#plugin-hooks-register-tools>, or directly on the command-line using the --functions argument to specify a block of Python code defining one or more functions - or a path to a Python file containing the same.

You can use tools with the LLM command-line tool <#usage-tools> or with the Python API <#python-api-tools>​.

Default tools

LLM includes some default tools for you to try out:

  • llm_version() returns the current version of LLM
  • llm_time() returns the current local and UTC time

Try them like this:

llm -T llm_version -T llm_time 'Give me the current time and LLM version' --td

Tips for implementing tools

Consult the register_tools() plugin hook <#plugin-hooks-register-tools> documentation for examples of how to implement tools in plugins.

If your plugin needs access to API secrets I recommend storing those using llm keys set api-name and then reading them using the llm.get_key() <#plugin-utilities-get-key> utility function. This avoids secrets being logged to the database as part of tool calls.

If your tool implementation needs to know which tool call invoked it - for example to key state against the unique tool_call_id - add a parameter named llm_tool_call to your function. It will be passed the llm.ToolCall object for the current invocation, and is hidden from the schema the model sees. See Accessing the tool call from inside a tool <#python-api-tools-llm-tool-call> for details.

Schemas

Large Language Models are very good at producing structured output as JSON or other formats. LLM's schemas feature allows you to define the exact structure of JSON data you want to receive from a model.

This feature is supported by models from OpenAI, Anthropic, Google Gemini and can be implemented for others via plugins <#advanced-model-plugins-schemas>​.

This page describes schemas used via the llm command-line tool. Schemas can also be used from the Python API <#python-api-schemas>​.

Schemas tutorial

In this tutorial we're going to use schemas to analyze some news stories.

But first, let's invent some dogs!

Getting started with dogs

LLMs are great at creating test data. Let's define a simple schema for a dog, using LLM's concise schema syntax​. We'll pass that to LLm with llm --schema and prompt it to "invent a cool dog":

llm --schema 'name, age int, one_sentence_bio' 'invent a cool dog'

I got back Ziggy:

{
  "name": "Ziggy",
  "age": 4,
  "one_sentence_bio": "Ziggy is a hyper-intelligent, bioluminescent dog who loves to perform tricks in the dark and guides his owner home using his glowing fur."
}

The response matched my schema, with name and one_sentence_bio string columns and an integer for age​.

We're using the default LLM model here - gpt-5.6-luna​. Add -m model to use another model - for example use -m gpt-5.6-sol to have GPT-5.6 Sol invent some dogs.

For a list of available models that support schemas, run this command:

llm models --schemas

Want several more dogs? You can pass in that same schema using --schema-multi and ask for several at once:

llm --schema-multi 'name, age int, one_sentence_bio' 'invent 3 really cool dogs'

Here's what I got:

{
  "items": [
    {
      "name": "Echo",
      "age": 3,
      "one_sentence_bio": "Echo is a sleek, silvery-blue Siberian Husky with mesmerizing blue eyes and a talent for mimicking sounds, making him a natural entertainer."
    },
    {
      "name": "Nova",
      "age": 2,
      "one_sentence_bio": "Nova is a vibrant, spotted Dalmatian with an adventurous spirit and a knack for agility courses, always ready to leap into action."
    },
    {
      "name": "Pixel",
      "age": 4,
      "one_sentence_bio": "Pixel is a playful, tech-savvy Poodle with a rainbow-colored coat, known for her ability to interact with smart devices and her love for puzzle toys."
    }
  ]
}

So that's the basic idea: we can feed in a schema and LLM will pass it to the underlying model and (usually) get back JSON that conforms to that schema.

This stuff gets a lot more useful when you start applying it to larger amounts of text, extracting structured details from unstructured content.

Extracting people from a news articles

We are going to extract details of the people who are mentioned in different news stories, and then use those to compile a database.

Let's start by compiling a schema. For each person mentioned we want to extract the following details:

  • Their name
  • The organization they work for
  • Their role
  • What we learned about them from the story

We will also record the article headline and the publication date, to make things easier for us later on.

Using LLM's custom, concise schema language, this time with newlines separating the individual fields (for the dogs example we used commas):

name: the person's name
organization: who they represent
role: their job title or role
learned: what we learned about them from this story
article_headline: the headline of the story
article_date: the publication date in YYYY-MM-DD

As you can see, this schema definition is pretty simple - each line has the name of a property we want to capture, then an optional: followed by a description, which doubles as instructions for the model.

The full syntax is described below - you can also include type information for things like numbers.

Let's run this against a news article.

Visit AP News <https://apnews.com/> and grab the URL to an article. I'm using this one:

https://apnews.com/article/trump-federal-employees-firings-a85d1aaf1088e050d39dcf7e3664bb9f

There's quite a lot of HTML on that page, possibly even enough to exceed GPT-4o mini's 128,000 token input limit. We'll use another tool called strip-tags <https://github.com/simonw/strip-tags> to reduce that. If you have uv <https://docs.astral.sh/uv/> installed you can call it using uvx strip-tags, otherwise you'll need to install it first:

uv tool install strip-tags
# Or "pip install" or "pipx install"

Now we can run this command to extract the people from that article:

curl 'https://apnews.com/article/trump-federal-employees-firings-a85d1aaf1088e050d39dcf7e3664bb9f' | \
  uvx strip-tags | \
  llm --schema-multi "
name: the person's name
organization: who they represent
role: their job title or role
learned: what we learned about them from this story
article_headline: the headline of the story
article_date: the publication date in YYYY-MM-DD
" --system 'extract people mentioned in this article'

The output I got started like this:

{
  "items": [
    {
      "name": "William Alsup",
      "organization": "U.S. District Court",
      "role": "Judge",
      "learned": "He ruled that the mass firings of probationary employees were likely unlawful and criticized the authority exercised by the Office of Personnel Management.",
      "article_headline": "Judge finds mass firings of federal probationary workers were likely unlawful",
      "article_date": "2025-02-26"
    },
    {
      "name": "Everett Kelley",
      "organization": "American Federation of Government Employees",
      "role": "National President",
      "learned": "He hailed the court's decision as a victory for employees who were illegally fired.",
      "article_headline": "Judge finds mass firings of federal probationary workers were likely unlawful",
      "article_date": "2025-02-26"
    }

This data has been logged to LLM's SQLite database <#logging>​. We can retrieve the data back out again using the llm logs <#logging-view> command like this:

llm logs -c --data

The -c flag means "use most recent conversation", and the --data flag outputs just the JSON data that was captured in the response.

We're going to want to use the same schema for other things. Schemas that we use are automatically logged to the database - we can view them using llm schemas:

llm schemas

Here's the output:

- id: 3b7702e71da3dd791d9e17b76c88730e
  summary: |
    {items: [{name, organization, role, learned, article_headline, article_date}]}
  usage: |
    1 time, most recently 2025-02-28T04:50:02.032081+00:00

To view the full schema, run that command with --full:

llm schemas --full

Which outputs:

- id: 3b7702e71da3dd791d9e17b76c88730e
  schema: |
    {
      "type": "object",
      "properties": {
        "items": {
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "name": {
                "type": "string",
                "description": "the person's name"
              },
    ...

That 3b7702e71da3dd791d9e17b76c88730e ID can be used to run the same schema again. Let's try that now on a different URL:

curl 'https://apnews.com/article/bezos-katy-perry-blue-origin-launch-4a074e534baa664abfa6538159c12987' | \
  uvx strip-tags | \
  llm --schema 3b7702e71da3dd791d9e17b76c88730e \
    --system 'extract people mentioned in this article'

Here we are using --schema because our schema ID already corresponds to an array of items.

The result starts like this:

{
  "items": [
    {
      "name": "Katy Perry",
      "organization": "Blue Origin",
      "role": "Singer",
      "learned": "Katy Perry will join the all-female celebrity crew for a spaceflight organized by Blue Origin.",
      "article_headline": "Katy Perry and Gayle King will join Jeff Bezos’ fiancee Lauren Sanchez on Blue Origin spaceflight",
      "article_date": "2023-10-15"
    },

One more trick: let's turn our schema and system prompt combination into a template <#prompt-templates>​.

llm --schema 3b7702e71da3dd791d9e17b76c88730e \
  --system 'extract people mentioned in this article' \
  --save people

This creates a new template called "people". We can confirm the template was created correctly using:

llm templates show people

Which will output the YAML version of the template looking like this:

name: people
schema_object:
    properties:
        items:
            items:
                properties:
                    article_date:
                        description: the publication date in YYYY-MM-DD
                        type: string
                    article_headline:
                        description: the headline of the story
                        type: string
                    learned:
                        description: what we learned about them from this story
                        type: string
                    name:
                        description: the person's name
                        type: string
                    organization:
                        description: who they represent
                        type: string
                    role:
                        description: their job title or role
                        type: string
                required:
                - name
                - organization
                - role
                - learned
                - article_headline
                - article_date
                type: object
            type: array
    required:
    - items
    type: object
system: extract people mentioned in this article

We can now run our people extractor against another fresh URL. Let's use one from The Guardian:

curl https://www.theguardian.com/commentisfree/2025/feb/27/billy-mcfarland-new-fyre-festival-fantasist | \
  strip-tags | llm -t people

Storing the schema in a template means we can just use llm -t people to run the prompt. Here's what I got back:

{
  "items": [
    {
      "name": "Billy McFarland",
      "organization": "Fyre Festival",
      "role": "Organiser",
      "learned": "Billy McFarland is known for organizing the infamous Fyre Festival and was sentenced to six years in prison for wire fraud related to it. He is attempting to revive the festival with Fyre 2.",
      "article_headline": "Welcome back Billy McFarland and a new Fyre festival. Shows you can’t keep a good fantasist down",
      "article_date": "2025-02-27"
    }
  ]
}

Depending on the model, schema extraction may work against images and PDF files as well.

I took a screenshot of part of this story in the Onion <https://theonion.com/mark-zuckerberg-insists-anyone-with-same-skewed-values-1826829272/> and saved it to the following URL:

https://static.simonwillison.net/static/2025/onion-zuck.jpg

We can pass that as an attachment <#usage-attachments> using the -a option. This time let's use GPT-4o:

llm -t people -a https://static.simonwillison.net/static/2025/onion-zuck.jpg -m gpt-4o

Which gave me back this:

{
  "items": [
    {
      "name": "Mark Zuckerberg",
      "organization": "Facebook",
      "role": "CEO",
      "learned": "He addressed criticism by suggesting anyone with similar values and thirst for power could make the same mistakes.",
      "article_headline": "Mark Zuckerberg Insists Anyone With Same Skewed Values And Unrelenting Thirst For Power Could Have Made Same Mistakes",
      "article_date": "2018-06-14"
    }
  ]
}

Now that we've extracted people from a number of different sources, let's load them into a database.

The llm logs <#logging-view> command has several features for working with logged JSON objects. Since we've been recording multiple objects from each page in an "items" array using our people template we can access those using the following command:

llm logs --schema t:people --data-key items

In place of t:people we could use the 3b7702e71da3dd791d9e17b76c88730e schema ID or even the original schema string instead, see specifying a schema​.

This command outputs newline-delimited JSON for every item that has been captured using the specified schema:

{"name": "Katy Perry", "organization": "Blue Origin", "role": "Singer", "learned": "She is one of the passengers on the upcoming spaceflight with Blue Origin."}
{"name": "Gayle King", "organization": "Blue Origin", "role": "TV Journalist", "learned": "She is participating in the upcoming Blue Origin spaceflight."}
{"name": "Lauren Sanchez", "organization": "Blue Origin", "role": "Helicopter Pilot and former TV Journalist", "learned": "She selected the crew for the Blue Origin spaceflight."}
{"name": "Aisha Bowe", "organization": "Engineering firm", "role": "Former NASA Rocket Scientist", "learned": "She is part of the crew for the spaceflight."}
{"name": "Amanda Nguyen", "organization": "Research Scientist", "role": "Activist and Scientist", "learned": "She is included in the crew for the upcoming Blue Origin flight."}
{"name": "Kerianne Flynn", "organization": "Movie Producer", "role": "Producer", "learned": "She will also be a passenger on the upcoming spaceflight."}
{"name": "Billy McFarland", "organization": "Fyre Festival", "role": "Organiser", "learned": "He was sentenced to six years in prison for wire fraud in 2018 and has launched a new festival called Fyre 2.", "article_headline": "Welcome back Billy McFarland and a new Fyre festival. Shows you can\u2019t keep a good fantasist down", "article_date": "2025-02-27"}
{"name": "Mark Zuckerberg", "organization": "Facebook", "role": "CEO", "learned": "He attempted to dismiss criticism by suggesting that anyone with similar values and thirst for power could have made the same mistakes.", "article_headline": "Mark Zuckerberg Insists Anyone With Same Skewed Values And Unrelenting Thirst For Power Could Have Made Same Mistakes", "article_date": "2018-06-14"}

If we add --data-array we'll get back a valid JSON array of objects instead:

llm logs --schema t:people --data-key items --data-array

Output starts:

[{"name": "Katy Perry", "organization": "Blue Origin", "role": "Singer", "learned": "She is one of the passengers on the upcoming spaceflight with Blue Origin."},
 {"name": "Gayle King", "organization": "Blue Origin", "role": "TV Journalist", "learned": "She is participating in the upcoming Blue Origin spaceflight."},

We can load this into a SQLite database using sqlite-utils <https://sqlite-utils.datasette.io/>, in particular the sqlite-utils insert <https://sqlite-utils.datasette.io/en/stable/cli.html#inserting-json-data> command.

uv tool install sqlite-utils
# or pip install or pipx install

Now we can pipe the JSON into that tool to create a database with a people table:

llm logs --schema t:people --data-key items --data-array | \
  sqlite-utils insert data.db people -

To see a table of the name, organization and role columns use sqlite-utils rows <https://sqlite-utils.datasette.io/en/stable/cli.html#returning-all-rows-in-a-table>:

sqlite-utils rows data.db people -t -c name -c organization -c role

Which produces:

name             organization        role
---------------  ------------------  -----------------------------------------
Katy Perry       Blue Origin         Singer
Gayle King       Blue Origin         TV Journalist
Lauren Sanchez   Blue Origin         Helicopter Pilot and former TV Journalist
Aisha Bowe       Engineering firm    Former NASA Rocket Scientist
Amanda Nguyen    Research Scientist  Activist and Scientist
Kerianne Flynn   Movie Producer      Producer
Billy McFarland  Fyre Festival       Organiser
Mark Zuckerberg  Facebook            CEO

We can also explore the database in a web interface using Datasette <https://datasette.io/>:

uvx datasette data.db
# Or install datasette first:
uv tool install datasette # or pip install or pipx install
datasette data.db

Visit http://127.0.0.1:8001/data/people to start navigating the data.

Using JSON schemas

The above examples have both used concise schema syntax​. LLM converts this format to JSON schema <https://json-schema.org/>, and you can use JSON schema directly yourself if you wish.

JSON schema covers the following:

  • The data types of fields (string, number, array, object, etc.)
  • Required vs. optional fields
  • Nested data structures
  • Constraints on values (minimum/maximum, patterns, etc.)
  • Descriptions of those fields - these can be used to guide the language model

Different models may support different subsets of the overall JSON schema language. You should experiment to figure out what works for the model you are using.

LLM recommends that the top level of the schema is an object, not an array, for increased compatibility across multiple models. I suggest using {"items": [array of objects]} if you want to return an array.

The dogs schema above, name, age int, one_sentence_bio, would look like this as a full JSON schema:

{
  "type": "object",
  "properties": {
    "name": {
      "type": "string"
    },
    "age": {
      "type": "integer"
    },
    "one_sentence_bio": {
      "type": "string"
    }
  },
  "required": [
    "name",
    "age",
    "one_sentence_bio"
  ]
}

This JSON can be passed directly to the --schema option, or saved in a file and passed as the filename.

llm --schema '{
  "type": "object",
  "properties": {
    "name": {
      "type": "string"
    },
    "age": {
      "type": "integer"
    },
    "one_sentence_bio": {
      "type": "string"
    }
  },
  "required": [
    "name",
    "age",
    "one_sentence_bio"
  ]
}' 'a surprising dog'

Example output:

{
  "name": "Baxter",
  "age": 3,
  "one_sentence_bio": "Baxter is a rescue dog who learned to skateboard and now performs tricks at local parks, astonishing everyone with his skill!"
}

Ways to specify a schema

LLM accepts schema definitions for both running prompts and exploring logged responses, using the --schema option.

This option can take multiple forms:

  • A string providing a JSON schema: --schema '{"type": "object", ...}'
  • A condensed schema definition: --schema 'name,age int'
  • The name or path of a file on disk containing a JSON schema: --schema dogs.schema.json
  • The hexadecimal ID of a previously logged schema: --schema 520f7aabb121afd14d0c6c237b39ba2d - these IDs can be found using the llm schemas command.
  • A schema that has been saved in a template <#prompt-templates-save>: --schema t:name-of-template, see Saving reusable schemas in templates​.

Concise LLM schema syntax

JSON schema's can be time-consuming to construct by hand. LLM also supports a concise alternative syntax for specifying a schema.

A simple schema for an object with two string properties called name and bio looks like this:

name, bio

You can include type information by adding a type indicator after the property name, separated by a space.

name, bio, age int

Supported types are int for integers, float for floating point numbers, str for strings (the default) and bool for true/false booleans.

To include a description of the field to act as a hint to the model, add one after a colon:

name: the person's name, age int: their age, bio: a short bio

If your schema is getting long you can switch from comma-separated to newline-separated, which also allows you to use commas in those descriptions:

name: the person's name
age int: their age
bio: a short bio, no more than three sentences

You can experiment with the syntax using the llm schemas dsl command, which converts the input into a JSON schema:

llm schemas dsl 'name, age int'

Output:

{
  "type": "object",
  "properties": {
    "name": {
      "type": "string"
    },
    "age": {
      "type": "integer"
    }
  },
  "required": [
    "name",
    "age"
  ]
}

The Python utility function llm.schema_dsl(schema) can be used to convert this syntax into the equivalent JSON schema dictionary when working with schemas in the Python API <#python-api-schemas>​.

Saving reusable schemas in templates

If you want to store a schema with a name so you can reuse it easily in the future, the easiest way to do so is to save it in a template <#prompt-templates-schemas>​.

The quickest way to do that is with the llm --save option:

llm --schema 'name, age int, one_sentence_bio' --save dog

Now you can use it like this:

llm --schema t:dog 'invent a dog'

Or:

llm --schema-multi t:dog 'invent three dogs'

Browsing logged JSON objects created using schemas

By default, all JSON produced using schemas is logged to a SQLite database <#logging>​. You can use special options to the llm logs command to extract just those JSON objects in a useful format.

The llm logs --schema X filter option can be used to filter just for responses that were created using the specified schema. You can pass the full schema JSON, a path to the schema on disk or the schema ID.

The --data option causes just the JSON data collected by that schema to be outputted, as newline-delimited JSON.

If you instead want a JSON array of objects (with starting and ending square braces) you can use --data-array instead.

Let's invent some dogs:

llm --schema-multi 'name, ten_word_bio' 'invent 3 cool dogs'
llm --schema-multi 'name, ten_word_bio' 'invent 2 cool dogs'

Having logged these cool dogs, you can see just the data that was returned by those prompts like this:

llm logs --schema-multi 'name, ten_word_bio' --data

We need to use --schema-multi here because we used that when we first created these records. The --schema option is also supported, and can be passed a filename or JSON schema or schema ID as well.

Output:

{"items": [{"name": "Robo", "ten_word_bio": "A cybernetic dog with laser eyes and super intelligence."}, {"name": "Flamepaw", "ten_word_bio": "Fire-resistant dog with a talent for agility and tricks."}]}
{"items": [{"name": "Bolt", "ten_word_bio": "Lightning-fast border collie, loves frisbee and outdoor adventures."}, {"name": "Luna", "ten_word_bio": "Mystical husky with mesmerizing blue eyes, enjoys snow and play."}, {"name": "Ziggy", "ten_word_bio": "Quirky pug who loves belly rubs and quirky outfits."}]}

Note that the dogs are nested in that "items" key. To access the list of items from that key use --data-key items:

llm logs --schema-multi 'name, ten_word_bio' --data-key items

Output:

{"name": "Bolt", "ten_word_bio": "Lightning-fast border collie, loves frisbee and outdoor adventures."}
{"name": "Luna", "ten_word_bio": "Mystical husky with mesmerizing blue eyes, enjoys snow and play."}
{"name": "Ziggy", "ten_word_bio": "Quirky pug who loves belly rubs and quirky outfits."}
{"name": "Robo", "ten_word_bio": "A cybernetic dog with laser eyes and super intelligence."}
{"name": "Flamepaw", "ten_word_bio": "Fire-resistant dog with a talent for agility and tricks."}

Finally, to output a JSON array instead of newline-delimited JSON use --data-array:

llm logs --schema-multi 'name, ten_word_bio' --data-key items --data-array

Output:

[{"name": "Bolt", "ten_word_bio": "Lightning-fast border collie, loves frisbee and outdoor adventures."},
 {"name": "Luna", "ten_word_bio": "Mystical husky with mesmerizing blue eyes, enjoys snow and play."},
 {"name": "Ziggy", "ten_word_bio": "Quirky pug who loves belly rubs and quirky outfits."},
 {"name": "Robo", "ten_word_bio": "A cybernetic dog with laser eyes and super intelligence."},
 {"name": "Flamepaw", "ten_word_bio": "Fire-resistant dog with a talent for agility and tricks."}]

Add --data-ids to include "response_id" and "conversation_id" fields in each of the returned objects reflecting the database IDs of the response and conversation they were a part of. This can be useful for tracking the source of each individual row.

llm logs --schema-multi 'name, ten_word_bio' --data-key items --data-ids

Output:

{"name": "Nebula", "ten_word_bio": "A cosmic puppy with starry fur, loves adventures in space.", "response_id": "01jn4dawj8sq0c6t3emf4k5ryx", "conversation_id": "01jn4daxk2sq0c6t3emf4k5aaa"}
{"name": "Echo", "ten_word_bio": "A clever hound with extraordinary hearing, master of hide-and-seek.", "response_id": "01jn4dawj8sq0c6t3emf4k5ryx", "conversation_id": "01jn4daxk2sq0c6t3emf4k5aaa"}
{"name": "Biscuit", "ten_word_bio": "An adorable chef dog, bakes treats that everyone loves.", "response_id": "01jn4dawj8sq0c6t3emf4k5ryx", "conversation_id": "01jn4daxk2sq0c6t3emf4k5aaa"}
{"name": "Cosmo", "ten_word_bio": "Galactic explorer, loves adventures and chasing shooting stars.", "response_id": "01jn4daycb3svj0x7kvp7zrp4q", "conversation_id": "01jn4dazk2sq0c6t3emf4k5bbb"}
{"name": "Pixel", "ten_word_bio": "Tech-savvy pup, builds gadgets and loves virtual playtime.", "response_id": "01jn4daycb3svj0x7kvp7zrp4q", "conversation_id": "01jn4dazk2sq0c6t3emf4k5bbb"}

If a row already has a property called "conversation_id" or "response_id" additional underscores will be appended to the ID key until it no longer overlaps with the existing keys.

The --id-gt $ID and --id-gte $ID options can be useful for ignoring logged schema data prior to a certain point, see Filtering past a specific ID <#logging-filter-id> for details.

Templates

A template can combine a prompt, system prompt, model, default model options, schema, and fragments into a single reusable unit.

Only one template can be used at a time. To compose multiple shorter pieces of prompts together consider using fragments <#fragments> instead.

Getting started with --save

The easiest way to create a template is using the --save template_name option.

Here's how to create a template for summarizing text:

llm '$input - summarize this' --save summarize

Put $input where you would like the user's input to be inserted. If you omit this their input will be added to the end of your regular prompt:

llm 'Summarize the following: ' --save summarize

You can also create templates using system prompts:

llm --system 'Summarize this' --save summarize

You can set the default model for a template using --model:

llm --system 'Summarize this' --model gpt-4o --save summarize

You can also save default options:

llm --system 'Speak in French' -o temperature 1.8 --save wild-french

If you want to include a literal $ sign in your prompt, use $$ instead:

llm --system 'Estimate the cost in $$ of this: $input' --save estimate

Use --tool/-T one or more times to add tools to the template:

llm -T llm_time --system 'Always include the current time in the answer' --save time

You can also use --functions to add Python function code directly to the template:

llm --functions 'def reverse_string(s): return s[::-1]' --system 'reverse any input' --save reverse
llm -t reverse 'Hello, world!'

Add --schema to bake a schema <#usage-schemas> into your template:

llm --schema dog.schema.json 'invent a dog' --save dog

If you add --extract the setting to  extract the first fenced code block <#usage-extract-fenced-code> will be persisted in the template.

llm --system 'write a Python function' --extract --save python-function
llm -t python-function 'calculate haversine distance between two points'

In each of these cases the template will be saved in YAML format in a dedicated directory on disk.

Using a template

You can execute a named template using the -t/--template option:

curl -s https://example.com/ | llm -t summarize

This can be combined with the -m option to specify a different model:

curl -s https://llm.datasette.io/en/latest/ | \
  llm -t summarize -m gpt-3.5-turbo-16k

Templates can also be specified as a direct path to a YAML file on disk:

llm -t path/to/template.yaml 'extra prompt here'

Or as a URL to a YAML file hosted online:

llm -t https://raw.githubusercontent.com/simonw/llm-templates/refs/heads/main/python-app.yaml \
  'Python app to pick a random line from a file'

The option can be repeated to combine templates. They are applied from left to right, so one template can provide model configuration and options while a later template provides or transforms the prompt:

llm -t model-and-options -t summarize 'Text to summarize'

Note that templates loaded via URLs will have any functions: keys ignored, to avoid accidentally executing arbitrary code. This restriction also applies to templates loaded via the template loaders plugin mechanism <#plugin-hooks-register-template-loaders>​.

Listing available templates

This command lists all available templates:

llm templates

The output looks something like this:

cmd        : system: reply with macos terminal commands only, no extra information
glados     : system: You are GlaDOS prompt: Summarize this:

Templates as YAML files

Templates are stored as YAML files on disk.

You can edit (or create) a YAML file for a template using the llm templates edit command:

llm templates edit summarize

This will open the system default editor.

Tip:

You can control which editor will be used here using the EDITOR environment variable - for example, to use VS Code:

export EDITOR="code -w"

Add that to your ~/.zshrc or ~/.bashrc file depending on which shell you use (zsh is the default on macOS since macOS Catalina in 2019).

You can create or edit template files directly in the templates directory. The location of this directory is shown by the llm templates path command:

llm templates path

Example output:

/Users/simon/Library/Application Support/io.datasette.llm/templates

A basic YAML template looks like this:

prompt: 'Summarize this: $input'

Or use YAML multi-line strings for longer inputs. I created this using llm templates edit steampunk:

prompt: >
    Summarize the following text.

    Insert frequent satirical steampunk-themed illustrative anecdotes.
    Really go wild with that.

    Text to summarize: $input

The prompt: > causes the following indented text to be treated as a single string, with newlines collapsed to spaces. Use prompt: | to preserve newlines.

Running that with llm -t steampunk against GPT-4o (via strip-tags <https://github.com/simonw/strip-tags> to remove HTML tags from the input and minify whitespace):

curl -s 'https://til.simonwillison.net/macos/imovie-slides-and-audio' | \
  strip-tags -m | llm -t steampunk -m gpt-4o
Output:

In a fantastical steampunk world, Simon Willison decided to merge an old MP3 recording with slides from the talk using iMovie. After exporting the slides as images and importing them into iMovie, he had to disable the default Ken Burns effect using the "Crop" tool. Then, Simon manually synchronized the audio by adjusting the duration of each image. Finally, he published the masterpiece to YouTube, with the whimsical magic of steampunk-infused illustrations leaving his viewers in awe.

System prompts

When working with models that support system prompts you can set a system prompt using a system: key like so:

system: Summarize this

If you specify only a system prompt you don't need to use the $input variable - llm will use the user's input as the whole of the regular prompt, which will then be processed using the instructions set in that system prompt.

You can combine system and regular prompts like so:

system: You speak like an excitable Victorian adventurer
prompt: 'Summarize this: $input'

Fragments

Templates can reference Fragments <#fragments> using the fragments: and system_fragments: keys. These should be a list of fragment URLs, filepaths or hashes:

fragments:
- https://example.com/robots.txt
- /path/to/file.txt
- 993fd38d898d2b59fd2d16c811da5bdac658faa34f0f4d411edde7c17ebb0680
system_fragments:
- https://example.com/systm-prompt.txt

Options

Default options can be set using the options: key:

name: wild-french
system: Speak in French
options:
  temperature: 1.8

Tools

The tools: key can provide a list of tool names from other plugins - either function names or toolbox specifiers:

name: time-plus
tools:
- llm_time
- Datasette("https://example.com/timezone-lookup")

The functions: key can provide a multi-line string of Python code defining additional functions:

name: my-functions
functions: |
  def reverse_string(s: str):
      return s[::-1]

  def greet(name: str):
      return f"Hello, {name}!"

Schemas

Use the schema_object: key to embed a JSON schema (as YAML) in your template. The easiest way to create these is with the llm --schema ... --save name-of-template command - the result should look something like this:

name: dogs
schema_object:
    properties:
        dogs:
            items:
                properties:
                    bio:
                        type: string
                    name:
                        type: string
                type: object
            type: array
    type: object

Additional template variables

Templates that work against the user's normal prompt input (content that is either piped to the tool via standard input or passed as a command-line argument) can use the $input variable.

You can use additional named variables. These will then need to be provided using the -p/--param option when executing the template.

Here's an example YAML template called recipe, which you can create using llm templates edit recipe:

prompt: |
    Suggest a recipe using ingredients: $ingredients

    It should be based on cuisine from this country: $country

This can be executed like so:

llm -t recipe -p ingredients 'sausages, milk' -p country Germany

My output started like this:

Recipe: German Sausage and Potato Soup

Ingredients:

  • 4 German sausages
  • 2 cups whole milk

This example combines input piped to the tool with additional parameters. Call this summarize:

system: Summarize this text in the voice of $voice

Then to run it:

curl -s 'https://til.simonwillison.net/macos/imovie-slides-and-audio' | \
  strip-tags -m | llm -t summarize -p voice GlaDOS

I got this:

My previous test subject seemed to have learned something new about iMovie. They exported keynote slides as individual images [...] Quite impressive for a human.

Specifying default parameters

When creating a template using the --save option you can pass -p name value to store the default values for parameters:

llm --system 'Summarize this text in the voice of $voice' \
  --model gpt-4o -p voice GlaDOS --save summarize

You can specify default values for parameters in the YAML using the defaults: key.

system: Summarize this text in the voice of $voice
defaults:
  voice: GlaDOS

When running without -p it will choose the default:

curl -s 'https://til.simonwillison.net/macos/imovie-slides-and-audio' | \
  strip-tags -m | llm -t summarize

But you can override the defaults with -p:

curl -s 'https://til.simonwillison.net/macos/imovie-slides-and-audio' | \
  strip-tags -m | llm -t summarize -p voice Yoda

I got this:

Text, summarize in Yoda's voice, I will: "Hmm, young padawan. Summary of this text, you seek. Hmmm. ...

Configuring code extraction

To configure the extract first fenced code block <#usage-extract-fenced-code> setting for the template, add this:

extract: true

Setting a default model for a template

Templates executed using llm -t template-name will execute using the default model that the user has configured for the tool - or gpt-5.6-luna if they have not configured their own default.

You can specify a new default model for a template using the model: key in the associated YAML. Here's a template called roast:

model: gpt-4o
system: roast the user at every possible opportunity, be succinct

Example:

llm -t roast 'How are you today?'

I'm doing great but with your boring questions, I must admit, I've seen more life in a cemetery.

Template loaders from plugins

LLM plugins can register prefixes <#plugin-hooks-register-template-loaders> that can be used to load templates from external sources.

llm-templates-github <https://github.com/simonw/llm-templates-github> is an example which adds a gh: prefix which can be used to load templates from GitHub.

You can install that plugin like this:

llm install llm-templates-github

Use the llm templates loaders command to see details of the registered loaders.

llm templates loaders

Output:

gh:
  Load a template from GitHub or local cache if available

  Format: username/repo/template_name (without the .yaml extension)
    or username/template_name which means username/llm-templates/template_name

Then you can then use it like this:

curl -sL 'https://llm.datasette.io/' | llm -t gh:simonw/summarize

The -sL flags to curl are used to follow redirects and suppress progress meters.

This command will fetch the content of the LLM index page and feed it to the template defined by summarize.yaml <https://github.com/simonw/llm-templates/blob/main/summarize.yaml> in the simonw/llm-templates <https://github.com/simonw/llm-templates> GitHub repository.

If two template loader plugins attempt to register the same prefix one of them will have _1 added to the end of their prefix. Use llm templates loaders to check if this has occurred.

Fragments

LLM prompts can optionally be composed out of fragments - reusable pieces of text that are logged just once to the database and can then be attached to multiple prompts.

These are particularly useful when you are working with long context models, which support feeding large amounts of text in as part of your prompt.

Fragments primarily exist to save space in the database, but may be used to support other features such as vendor prompt caching as well.

Fragments can be specified using several different mechanisms:

  • URLs to text files online
  • Paths to text files on disk
  • Aliases that have been attached to a specific fragment
  • Hash IDs of stored fragments, where the ID is the SHA256 hash of the fragment content
  • Fragments that are provided by custom plugins - these look like plugin-name:argument

Using fragments in a prompt

Use the -f/--fragment option to specify one or more fragments to be used as part of your prompt:

llm -f https://llm.datasette.io/robots.txt "Explain this robots.txt file in detail"

Here we are specifying a fragment using a URL. The contents of that URL will be included in the prompt that is sent to the model, prepended prior to the prompt text.

The URL will be fetched with the user-agent llm/0.33 (https://llm.datasette.io/)​.

The -f option can be used multiple times to combine together multiple fragments.

Fragments can also be files on disk, for example:

llm -f setup.py 'extract the metadata'

Use - to specify a fragment that is read from standard input:

llm -f - 'extract the metadata' < setup.py

This will read the contents of setup.py from standard input and use it as a fragment.

Fragments can also be used as part of your system prompt. Use --sf value or --system-fragment value instead of -f​.

Using fragments in chat

The chat command also supports the -f and --sf arguments to start a chat with fragments.

llm chat -f my_doc.txt
Chatting with gpt-4
Type 'exit' or 'quit' to exit
Type '!multi' to enter multiple lines, then '!end' to finish
Type '!edit' to open your default editor and modify the prompt.
Type '!fragment <my_fragment> [<another_fragment> ...]' to insert one or more fragments
> Explain this document to me

Fragments can also be added during a chat conversation using the !fragment <my_fragment> command.

Chatting with gpt-4
Type 'exit' or 'quit' to exit
Type '!multi' to enter multiple lines, then '!end' to finish
Type '!edit' to open your default editor and modify the prompt.
Type '!fragment <my_fragment> [<another_fragment> ...]' to insert one or more fragments
> !fragment https://llm.datasette.io/en/stable/fragments.html

This can be combined with !multi:

> !multi
Explain the difference between fragments and templates to me
!fragment https://llm.datasette.io/en/stable/fragments.html https://llm.datasette.io/en/stable/templates.html
!end

Any !fragment lines found in a prompt created with !edit will not be parsed.

Browsing fragments

You can view a truncated version of the fragments you have previously stored in your database with the llm fragments command:

llm fragments

The output from that command looks like this:

- hash: 0d6e368f9bc21f8db78c01e192ecf925841a957d8b991f5bf9f6239aa4d81815
  aliases: []
  datetime_utc: '2025-04-06 07:36:53'
  source: https://raw.githubusercontent.com/simonw/llm-docs/refs/heads/main/llm/0.22.txt
  content: |-
    <documents>
    <document index="1">
    <source>docs/aliases.md</source>
    <document_content>
    (aliases)=
    #...
- hash: 16b686067375182573e2aa16b5bfc1e64d48350232535d06444537e51f1fd60c
  aliases: []
  datetime_utc: '2025-04-06 23:03:47'
  source: simonw/files-to-prompt/pyproject.toml
  content: |-
    [project]
    name = "files-to-prompt"
    version = "0.6"
    description = "Concatenate a directory full of...

Those long hash values are IDs that can be used to reference a fragment in the future:

llm -f 16b686067375182573e2aa16b5bfc1e64d48350232535d06444537e51f1fd60c 'Extract metadata'

Use -q searchterm one or more times to search for fragments that match a specific set of search terms.

To view the full content of a fragment use llm fragments show:

llm fragments show 0d6e368f9bc21f8db78c01e192ecf925841a957d8b991f5bf9f6239aa4d81815

Setting aliases for fragments

You can assign aliases to fragments that you use often using the llm fragments set command:

llm fragments set mydocs ./docs.md

To remove an alias, use llm fragments remove:

llm fragments remove mydocs

You can then use that alias in place of the fragment hash ID:

llm -f mydocs 'How do I access metadata?'

Use llm fragments --aliases to see a full list of fragments that have been assigned aliases:

llm fragments --aliases

Viewing fragments in your logs

The llm logs command lists the fragments that were used for a prompt. By default these are listed as fragment hash IDs, but you can use the --expand option to show the full content of each fragment.

This command will show the expanded fragments for your most recent conversation:

llm logs -c --expand

You can filter for logs that used a specific fragment using the -f/--fragment option:

llm logs -c -f 0d6e368f9bc21f8db78c01e192ecf925841a957d8b991f5bf9f6239aa4d81815

This accepts URLs, file paths, aliases, and hash IDs.

Multiple -f options will return responses that used all of the specified fragments.

Fragments are returned by llm logs --json as well. By default these are truncated but you can add the -e/--expand option to show the full content of each fragment.

llm logs -c --json --expand

Using fragments from plugins

LLM plugins can provide custom fragment loaders which do useful things.

One example is the llm-fragments-github plugin <https://github.com/simonw/llm-fragments-github>​. This can convert the files from a public GitHub repository into a list of fragments, allowing you to ask questions about the full repository.

Here's how to try that out:

llm install llm-fragments-github
llm -f github:simonw/s3-credentials 'Suggest new features for this tool'

This plugin turns a single call to -f github:simonw/s3-credentials into multiple fragments, one for every text file in the simonw/s3-credentials <https://github.com/simonw/s3-credentials> GitHub repository.

Running llm logs -c will show that this prompt incorporated 26 fragments, one for each file.

Running llm logs -c --usage --expand (shortcut: llm logs -cue) includes token usage information and turns each fragment ID into a full copy of that file. Here's the output of that command <https://gist.github.com/simonw/c9bbbc5f6560b01f4b7882ac0194fb25>​.

Fragment plugins can return attachments <#usage-attachments> (such as images) as well.

See the register_fragment_loaders() plugin hook <#plugin-hooks-register-fragment-loaders> documentation for details on writing your own custom fragment plugin.

Listing available fragment prefixes

The llm fragments loaders command shows all prefixes that have been installed by plugins, along with their documentation:

llm install llm-fragments-github
llm fragments loaders

Example output:

github:
  Load files from a GitHub repository as fragments

  Argument is a GitHub repository URL or username/repository

issue:
  Fetch GitHub issue and comments as Markdown

  Argument is either "owner/repo/NUMBER"
  or "https://github.com/owner/repo/issues/NUMBER"

Model aliases

LLM supports model aliases, which allow you to refer to a model by a short name instead of its full ID.

Listing aliases

To list current aliases, run this:

llm aliases

Example output:

4o                  : gpt-4o
4o-mini             : gpt-4o-mini
4.1                 : gpt-4.1
4.1-mini            : gpt-4.1-mini
4.1-nano            : gpt-4.1-nano
3.5                 : gpt-3.5-turbo
chatgpt             : gpt-3.5-turbo
chatgpt-16k         : gpt-3.5-turbo-16k
3.5-16k             : gpt-3.5-turbo-16k
4                   : gpt-4
gpt4                : gpt-4
gpt-4-turbo-preview : gpt-4-turbo
4-turbo             : gpt-4-turbo
4t                  : gpt-4-turbo
3.5-instruct        : gpt-3.5-turbo-instruct
chatgpt-instruct    : gpt-3.5-turbo-instruct
ada                 : text-embedding-ada-002 (embedding)
ada-002             : text-embedding-ada-002 (embedding)
3-small             : text-embedding-3-small (embedding)
3-large             : text-embedding-3-large (embedding)
3-small-512         : text-embedding-3-small-512 (embedding)
3-large-256         : text-embedding-3-large-256 (embedding)
3-large-1024        : text-embedding-3-large-1024 (embedding)

Add --json to get that list back as JSON:

llm aliases list --json

Example output:

{
    "3.5": "gpt-3.5-turbo",
    "chatgpt": "gpt-3.5-turbo",
    "4": "gpt-4",
    "gpt4": "gpt-4",
    "ada": "ada-002"
}

Adding a new alias

The llm aliases set <alias> <model-id> command can be used to add a new alias:

llm aliases set luna gpt-5.6-luna

You can also pass one or more -q search options to set an alias on the first model matching those search terms:

llm aliases set luna -q gpt -q luna

Now you can run the gpt-5.6-luna model using the luna alias like this:

llm -m luna 'An epic Greek-style saga about a cheesecake that builds a SQL database from scratch'

Aliases can be set for both regular models and embedding models <#embeddings> using the same command. To set an alias of oai for the OpenAI ada-002 embedding model use this:

llm aliases set oai ada-002

Now you can embed a string using that model like so:

llm embed -c 'hello world' -m oai

Output:

[-0.014945968054234982, 0.0014304015785455704, ...]

Removing an alias

The llm aliases remove <alias> command will remove the specified alias:

llm aliases remove mini

Viewing the aliases file

Aliases are stored in an aliases.json file in the LLM configuration directory.

To see the path to that file, run this:

llm aliases path

To view the content of that file, run this:

cat "$(llm aliases path)"

Embeddings

Embedding models allow you to take a piece of text - a word, sentence, paragraph or even a whole article, and convert that into an array of floating point numbers.

This floating point array is called an "embedding vector", and works as a numerical representation of the semantic meaning of the content in a many-multi-dimensional space.

By calculating the distance between embedding vectors, we can identify which content is semantically "nearest" to other content.

This can be used to build features like related article lookups. It can also be used to build semantic search, where a user can search for a phrase and get back results that are semantically similar to that phrase even if they do not share any exact keywords.

Some embedding models like CLIP <https://github.com/simonw/llm-clip> can even work against binary files such as images. These can be used to search for images that are similar to other images, or to search for images that are semantically similar to a piece of text.

LLM supports multiple embedding models through plugins <#plugins>​. Once installed, an embedding model can be used on the command-line or via the Python API to calculate and store embeddings for content, and then to perform similarity searches against those embeddings.

See LLM now provides tools for working with embeddings <https://simonwillison.net/2023/Sep/4/llm-embeddings/> for an extended explanation of embeddings, why they are useful and what you can do with them.

Embedding with the CLI

LLM provides command-line utilities for calculating and storing embeddings for pieces of content.

llm embed

The llm embed command can be used to calculate embedding vectors for a string of content. These can be returned directly to the terminal, stored in a SQLite database, or both.

Returning embeddings to the terminal

The simplest way to use this command is to pass content to it using the -c/--content option, like this:

llm embed -c 'This is some content' -m 3-small

-m 3-small specifies the OpenAI text-embedding-3-small model. You will need to have set an OpenAI API key using llm keys set openai for this to work.

You can pass an API key directly using the --key option instead of relying on a stored or environment variable key. This option is also available for llm embed-multi​.

You can install plugins to access other models. The llm-sentence-transformers <https://github.com/simonw/llm-sentence-transformers> plugin can be used to run models on your own laptop, such as the MiniLM-L6 <https://huggingface.co/sentence-transformers/all-MiniLM-L6-v2> model:

llm install llm-sentence-transformers
llm embed -c 'This is some content' -m sentence-transformers/all-MiniLM-L6-v2

The llm embed command returns a JSON array of floating point numbers directly to the terminal:

[0.123, 0.456, 0.789...]

You can omit the -m/--model option if you set a default embedding model​.

You can also set the LLM_EMBEDDING_MODEL environment variable to set a default model for all llm embed commands in the current shell session:

export LLM_EMBEDDING_MODEL=3-small
llm embed -c 'This is some content'

LLM also offers a binary storage format for embeddings, described in embeddings storage format <#embeddings-storage>​.

You can output embeddings using that format as raw bytes using --format blob, or in hexadecimal using --format hex, or in Base64 using --format base64:

llm embed -c 'This is some content' -m 3-small --format base64

This outputs:

8NGzPFtdgTqHcZw7aUT6u+++WrwwpZo8XbSxv...

Some models such as llm-clip <https://github.com/simonw/llm-clip> can run against binary data. You can pass in binary data using the -i and --binary options:

llm embed --binary -m clip -i image.jpg

Or from standard input like this:

cat image.jpg | llm embed --binary -m clip -i -

Storing embeddings in SQLite

Embeddings are much more useful if you store them somewhere, so you can calculate similarity scores between different embeddings later on.

LLM includes the concept of a collection of embeddings. A collection groups together a set of stored embeddings created using the same model, each with a unique ID within that collection.

Embeddings also store a hash of the content that was embedded. This hash is later used to avoid calculating duplicate embeddings for the same content.

First, we'll set a default model so we don't have to keep repeating it:

llm embed-models default 3-small

The llm embed command can store results directly in a named collection like this:

llm embed quotations philkarlton-1 -c \
  'There are only two hard things in Computer Science: cache invalidation and naming things'

This stores the given text in the quotations collection under the key philkarlton-1​.

You can also pipe content to standard input, like this:

cat one.txt | llm embed files one

This will store the embedding for the contents of one.txt in the files collection under the key one​.

A collection will be created the first time you mention it.

Collections have a fixed embedding model, which is the model that was used for the first embedding stored in that collection.

In the above example this would have been the default embedding model at the time that the command was run.

The following example stores the embedding for the string "my happy hound" in a collection called phrases under the key hound and using the model 3-small:

llm embed phrases hound -m 3-small -c 'my happy hound'

By default, the SQLite database used to store embeddings is the embeddings.db in the user content directory managed by LLM.

You can see the path to this directory by running llm collections path​.

You can store embeddings in a different SQLite database by passing a path to it using the -d/--database option to llm embed​. If this file does not exist yet the command will create it:

llm embed phrases hound -d my-embeddings.db -c 'my happy hound'

This creates a database file called my-embeddings.db in the current directory.

Storing content and metadata

By default, only the entry ID and the embedding vector are stored in the database table.

You can store a copy of the original text in the content column by passing the --store option:

llm embed phrases hound -c 'my happy hound' --store

You can also store a JSON object containing arbitrary metadata in the metadata column by passing the --metadata option. This example uses both --store and --metadata options:

llm embed phrases hound \
  -m 3-small \
  -c 'my happy hound' \
  --metadata '{"name": "Hound"}' \
  --store

Data stored in this way will be returned by calls to llm similar, for example:

llm similar phrases -c 'hound'
{"id": "hound", "score": 0.8484683588631485, "content": "my happy hound", "metadata": {"name": "Hound"}}

llm embed-multi

The llm embed command embeds a single string at a time.

llm embed-multi can be used to embed multiple strings at once, taking advantage of any efficiencies that the embedding model may provide when processing multiple strings.

This command can be called in one of three ways:

  1. With a CSV, TSV, JSON or newline-delimited JSON file
  2. With a SQLite database and a SQL query
  3. With one or more paths to directories, each accompanied by a glob pattern

All three mechanisms support these options:

  • -m model_id to specify the embedding model to use
  • -d database.db to specify a different database file to store the embeddings in
  • --store to store the original content in the embeddings table in addition to the embedding vector
  • --prefix to prepend a prefix to the stored ID of each item
  • --prepend to prepend a string to the content before embedding
  • --batch-size SIZE to process embeddings in batches of the specified size

The --prepend option is useful for embedding models that require you to prepend a special token to the content before embedding it. nomic-embed-text-v2-moe <https://huggingface.co/nomic-ai/nomic-embed-text-v2-moe> for example requires documents to be prepended 'search_document: ' and search queries to be prepended 'search_query: '​.

Embedding data from a CSV, TSV or JSON file

You can embed data from a CSV, TSV or JSON file by passing that file to the command as the second option, after the collection name.

Your file must contain at least two columns. The first one is expected to contain the ID of the item, and any subsequent columns will be treated as containing content to be embedded.

An example CSV file might look like this:

id,content
one,This is the first item
two,This is the second item

TSV would use tabs instead of commas.

JSON files can be structured like this:

[
  {"id": "one", "content": "This is the first item"},
  {"id": "two", "content": "This is the second item"}
]

Or as newline-delimited JSON like this:

{"id": "one", "content": "This is the first item"}
{"id": "two", "content": "This is the second item"}

In each of these cases the file can be passed to llm embed-multi like this:

llm embed-multi items mydata.csv

The first argument is the name of the collection, the second is the filename.

You can also pipe content to standard input of the tool using -:

cat mydata.json | llm embed-multi items -

LLM will attempt to detect the format of your data automatically. If this doesn't work you can specify the format using the --format option. This is required if you are piping newline-delimited JSON to standard input.

cat mydata.json | llm embed-multi items - --format nl

Other supported --format options are csv, tsv and json​.

This example embeds the data from a JSON file in a collection called items in database called docs.db using the 3-small model and stores the original content in the embeddings table as well, adding a prefix of my-items/ to each ID:

llm embed-multi items mydata.json \
  -d docs.db \
  -m 3-small \
  --prefix my-items/ \
  --store

Embedding data from a SQLite database

You can embed data from a SQLite database using --sql, optionally combined with --attach to attach an additional database.

If you are storing embeddings in the same database as the source data, you can do this:

llm embed-multi docs \
  -d docs.db \
  --sql 'select id, title, content from documents' \
  -m 3-small

The docs.db database here contains a documents table, and we want to embed the title and content columns from that table and store the results back in the same database.

To load content from a database other than the one you are using to store embeddings, attach it with the --attach option and use alias.table in your SQLite query:

llm embed-multi docs \
  -d embeddings.db \
  --attach other other.db \
  --sql 'select id, title, content from other.documents' \
  -m 3-small

Embedding data from files in directories

LLM can embed the content of every text file in a specified directory, using the file's path and name as the ID.

Consider a directory structure like this:

docs/aliases.md
docs/contributing.md
docs/embeddings/binary.md
docs/embeddings/cli.md
docs/embeddings/index.md
docs/index.md
docs/logging.md
docs/plugins/directory.md
docs/plugins/index.md

To embed all of those documents, you can run the following:

llm embed-multi documentation \
  -m 3-small \
  --files docs '**/*.md' \
  -d documentation.db \
  --store

Here --files docs '**/*.md' specifies that the docs directory should be scanned for files matching the **/*.md glob pattern - which will match Markdown files in any nested directory.

The result of the above command is a embeddings table with the following IDs:

aliases.md
contributing.md
embeddings/binary.md
embeddings/cli.md
embeddings/index.md
index.md
logging.md
plugins/directory.md
plugins/index.md

Each corresponding to embedded content for the file in question.

The --prefix option can be used to add a prefix to each ID:

llm embed-multi documentation \
  -m 3-small \
  --files docs '**/*.md' \
  -d documentation.db \
  --store \
  --prefix llm-docs/

This will result in the following IDs instead:

llm-docs/aliases.md
llm-docs/contributing.md
llm-docs/embeddings/binary.md
llm-docs/embeddings/cli.md
llm-docs/embeddings/index.md
llm-docs/index.md
llm-docs/logging.md
llm-docs/plugins/directory.md
llm-docs/plugins/index.md

Files are assumed to be utf-8, but LLM will fall back to latin-1 if it encounters an encoding error. You can specify a different set of encodings using the --encoding option.

This example will try utf-16 first and then mac_roman before falling back to latin-1:

llm embed-multi documentation \
  -m 3-small \
  --files docs '**/*.md' \
  -d documentation.db \
  --encoding utf-16 \
  --encoding mac_roman \
  --encoding latin-1

If a file cannot be read it will be logged to standard error but the script will keep on running.

If you are embedding binary content such as images for use with CLIP, add the --binary option:

llm embed-multi photos \
  -m clip \
  --files photos/ '*.jpeg' --binary

llm similar

The llm similar command searches a collection of embeddings for the items that are most similar to a given or item ID, based on cosine similarity <https://en.wikipedia.org/wiki/Cosine_similarity>​.

This currently uses a slow brute-force approach which does not scale well to large collections. See issue 216 <https://github.com/simonw/llm/issues/216> for plans to add a more scalable approach via vector indexes provided by plugins.

To search the quotations collection for items that are semantically similar to 'computer science':

llm similar quotations -c 'computer science'

This embeds the provided string and returns a newline-delimited list of JSON objects like this:

{"id": "philkarlton-1", "score": 0.8323904531677017, "content": null, "metadata": null}

Use -p/--plain to get back results in plain text instead of JSON:

llm similar quotations -c 'computer science' -p

Example output:

philkarlton-1 (0.8323904531677017)

You can compare against text stored in a file using -i filename:

llm similar quotations -i one.txt

Or feed text to standard input using -i -:

echo 'computer science' | llm similar quotations -i -

When using a model like CLIP, you can find images similar to an input image using -i filename with --binary:

llm similar photos -i image.jpg --binary

You can filter results to only show IDs that begin with a specific prefix using --prefix:

llm similar quotations --prefix 'movies/' -c 'star wars'

llm embed-models

To list all available embedding models, including those provided by plugins, run this command:

llm embed-models

The output should look something like this:

OpenAIEmbeddingModel: text-embedding-ada-002 (aliases: ada, ada-002)
OpenAIEmbeddingModel: text-embedding-3-small (aliases: 3-small)
OpenAIEmbeddingModel: text-embedding-3-large (aliases: 3-large)
​...

Add -q one or more times to search for models matching those terms:

llm embed-models -q 3-small

llm embed-models default

This command can be used to get and set the default embedding model.

This will return the name of the current default model:

llm embed-models default

You can set a different default like this:

llm embed-models default 3-small

This will set the default model to OpenAI's 3-small model.

Any of the supported aliases for a model can be passed to this command.

You can unset the default model using --remove-default:

llm embed-models default --remove-default

When no default model is set, the llm embed and llm embed-multi commands will require that a model is specified using -m/--model​.

llm collections list

To list all of the collections in the embeddings database, run this command:

llm collections list

Add --json for JSON output:

llm collections list --json

Add -d/--database to specify a different database file:

llm collections list -d my-embeddings.db

llm collections delete

To delete a collection from the database, run this:

llm collections delete collection-name

Pass -d to specify a different database file:

llm collections delete collection-name -d my-embeddings.db

Using embeddings from Python

You can load an embedding model using its model ID or alias like this:

import llm

embedding_model = llm.get_embedding_model("3-small")

To embed a string, returning a Python list of floating point numbers, use the ​.embed() method:

vector = embedding_model.embed("my happy hound")

You can pass an API key directly using key=​. This can be either the key itself or the alias of a key stored using llm keys set:

vector = embedding_model.embed("my happy hound", key="sk-...")

If the embedding model can handle binary input, you can call ​.embed() with a byte string instead. You can check the supports_binary property to see if this is supported:

from pathlib import Path

if embedding_model.supports_binary:
    vector = embedding_model.embed(Path("my-image.jpg").read_bytes())

The embedding_model.supports_text property indicates if the model supports text input.

Many embeddings models are more efficient when you embed multiple strings or binary strings at once. To embed multiple strings at once, use the ​.embed_multi() method:

vectors = list(embedding_model.embed_multi(["my happy hound", "my dissatisfied cat"]))

This returns a generator that yields one embedding vector per string.

embed_multi() accepts the same key= argument as embed()​.

Embeddings are calculated in batches. By default all items will be processed in a single batch, unless the underlying embedding model has defined its own preferred batch size. You can pass a custom batch size using batch_size=N, for example:

vectors = list(embedding_model.embed_multi(lines_from_file, batch_size=20))

Working with collections

The llm.Collection class can be used to work with collections of embeddings from Python code.

A collection is a named group of embedding vectors, each stored along with their IDs in a SQLite database table.

To work with embeddings in this way you will need an instance of a sqlite-utils Database <https://sqlite-utils.datasette.io/en/stable/python-api.html#connecting-to-or-creating-a-database> object. You can then pass that to the llm.Collection constructor along with the unique string name of the collection and the ID of the embedding model you will be using with that collection:

import sqlite_utils
import llm

# This collection will use an in-memory database that will be
# discarded when the Python process exits
collection = llm.Collection("entries", model_id="3-small")

# Or you can persist the database to disk like this:
db = sqlite_utils.Database("my-embeddings.db")
collection = llm.Collection("entries", db, model_id="3-small")

# You can pass a model directly using model= instead of model_id=
embedding_model = llm.get_embedding_model("3-small")
collection = llm.Collection("entries", db, model=embedding_model)

If the collection already exists in the database you can omit the model or model_id argument - the model ID will be read from the collections table.

To embed a single string and store it in the collection, use the embed() method:

collection.embed("hound", "my happy hound")

This stores the embedding for the string "my happy hound" in the entries collection under the key hound​.

You can pass an API key directly using key="..."​. The collection.embed_multi() and collection.embed_multi_with_metadata() methods accept this argument too.

Add store=True to store the text content itself in the database table along with the embedding vector.

To attach additional metadata to an item, pass a JSON-compatible dictionary as the metadata= argument:

collection.embed("hound", "my happy hound", metadata={"name": "Hound"}, store=True)

This additional metadata will be stored as JSON in the metadata column of the embeddings database table.

Storing embeddings in bulk

The collection.embed_multi() method can be used to store embeddings for multiple items at once. This can be more efficient for some embedding models.

collection.embed_multi(
    [
        ("hound", "my happy hound"),
        ("cat", "my dissatisfied cat"),
    ],
    # Add this to store the strings in the content column:
    store=True,
)

To include metadata to be stored with each item, call embed_multi_with_metadata():

collection.embed_multi_with_metadata(
    [
        ("hound", "my happy hound", {"name": "Hound"}),
        ("cat", "my dissatisfied cat", {"name": "Cat"}),
    ],
    # This can also take the store=True argument:
    store=True,
)

The batch_size= argument defaults to 100, and will be used unless the embedding model itself defines a lower batch size. You can adjust this if you are having trouble with memory while embedding large collections:

collection.embed_multi(
    (
        (i, line)
        for i, line in enumerate(lines_in_file)
    ),
    batch_size=10
)

Collection class reference

A collection instance has the following properties and methods:

  • id - the integer ID of the collection in the database
  • name - the string name of the collection (unique in the database)
  • model_id - the string ID of the embedding model used for this collection
  • model() - returns the EmbeddingModel instance, based on that model_id
  • count() - returns the integer number of items in the collection
  • embed(id: str, value: str | bytes, metadata: dict[str, Any] | None = None, store: bool = False, *, key: str | None = None) - embeds the given value and stores it in the collection under the given ID. Can optionally include metadata (stored as JSON), store the text or binary content itself in the database table and pass an API key or stored key alias.
  • embed_multi(entries: Iterable[tuple[str, str | bytes]], store: bool = False, batch_size: int = 100, *, key: str | None = None) - see above
  • embed_multi_with_metadata(entries: Iterable[tuple[str, str | bytes, dict[str, Any] | None]], store: bool = False, batch_size: int = 100, *, key: str | None = None) - see above
  • similar(value: str | bytes, number: int = 10, prefix: str | None = None) - returns a list of entries that are most similar to the embedding of the given value
  • similar_by_id(id: str, number: int = 10, prefix: str | None = None) - returns a list of entries that are most similar to the embedding of the item with the given ID
  • similar_by_vector(vector: list[float], number: int = 10, skip_id: str | None = None, prefix: str | None = None) - returns a list of entries that are most similar to the given embedding vector, optionally skipping the entry with the given ID
  • delete() - deletes the collection and its embeddings from the database

There is also a Collection.exists(db, name) class method which returns a boolean value and can be used to determine if a collection exists or not in a database:

if Collection.exists(db, "entries"):
    print("The entries collection exists")

Retrieving similar items

Once you have populated a collection of embeddings you can retrieve the entries that are most similar to a given string using the similar() method.

This method uses a brute force approach, calculating distance scores against every document. This is fine for small collections, but will not scale to large collections. See issue 216 <https://github.com/simonw/llm/issues/216> for plans to add a more scalable approach via vector indexes provided by plugins.

for entry in collection.similar("hound"):
    print(entry.id, entry.score)

The string will first by embedded using the model for the collection.

The entry object returned is an object with the following properties:

  • id - the string ID of the item
  • score - the floating point similarity score between the item and the query string
  • content - the string text content of the item, if it was stored - or None
  • metadata - the dictionary (from JSON) metadata for the item, if it was stored - or None

This defaults to returning the 10 most similar items. You can change this by passing a different number= argument:

for entry in collection.similar("hound", number=5):
    print(entry.id, entry.score)

The similar_by_id() method takes the ID of another item in the collection and returns the most similar items to that one, based on the embedding that has already been stored for it:

for entry in collection.similar_by_id("cat"):
    print(entry.id, entry.score)

The item itself is excluded from the results.

SQL schema

Here's the SQL schema used by the embeddings database:

CREATE TABLE "collections" (
   "id" INTEGER PRIMARY KEY,
   "name" TEXT,
   "model" TEXT
)
CREATE TABLE "embeddings" (
   "collection_id" INTEGER REFERENCES "collections"("id"),
   "id" TEXT,
   "embedding" BLOB,
   "content" TEXT,
   "content_blob" BLOB,
   "content_hash" BLOB,
   "metadata" TEXT,
   "updated" INTEGER,
   PRIMARY KEY ("collection_id", "id")
)

Writing plugins to add new embedding models

Read the plugin tutorial <#tutorial-model-plugin> for details on how to develop and package a plugin.

This page shows an example plugin that implements and registers a new embedding model.

There are two components to an embedding model plugin:

  1. An implementation of the register_embedding_models() hook, which takes a register callback function and calls it to register the new model with the LLM plugin system.
  2. A class that extends the llm.EmbeddingModel abstract base class.

    The only required method on this class is embed_batch(texts), which takes an iterable of strings and returns an iterator over lists of floating point numbers.

The following example uses the sentence-transformers <https://github.com/UKPLab/sentence-transformers> package to provide access to the MiniLM-L6 <https://huggingface.co/sentence-transformers/all-MiniLM-L6-v2> embedding model.

class llm.EmbeddingModel
embed(item: str | bytes, *, key: str | None = None) -> list[float]

Embed a single text string or binary blob, return a list of floats

abstractmethod embed_batch(items: Iterable[str | bytes], *, key: str | None = None) -> Iterator[list[float]]

Embed a batch of strings or blobs, return a list of lists of floats

embed_multi(items: Iterable[str | bytes], batch_size: int | None = None, *, key: str | None = None) -> Iterator[list[float]]

Embed multiple items in batches according to the model batch_size

import llm
from sentence_transformers import SentenceTransformer


@llm.hookimpl
def register_embedding_models(register):
    model_id = "sentence-transformers/all-MiniLM-L6-v2"
    register(SentenceTransformerModel(model_id, model_id), aliases=("all-MiniLM-L6-v2",))


class SentenceTransformerModel(llm.EmbeddingModel):
    def __init__(self, model_id, model_name):
        self.model_id = model_id
        self.model_name = model_name
        self._model = None

    def embed_batch(self, texts):
        if self._model is None:
            self._model = SentenceTransformer(self.model_name)
        results = self._model.encode(texts)
        return (list(map(float, result)) for result in results)

Embedding models that call a hosted API should set needs_key and optionally key_env_var, then accept a keyword-only key= argument in embed_batch()​. LLM resolves explicit keys, stored key aliases and environment variables before calling this method:

class HostedEmbeddingModel(llm.EmbeddingModel):
    model_id = "hosted-embedding-model"
    needs_key = "hosted"
    key_env_var = "HOSTED_API_KEY"

    def embed_batch(self, texts, *, key=None):
        # key is the resolved API key
        results = hosted_client.embed(texts, api_key=key)
        return (list(map(float, result)) for result in results)

The key= value can come from llm embed --key, llm embed-multi --key or the Python embed(..., key=) and embed_multi(..., key=) methods. For compatibility, LLM also supports older plugins whose embed_batch() method does not accept key= by temporarily exposing the resolved value as self.key​.

Once installed, the model provided by this plugin can be used with the llm embed <#embeddings-cli-embed> command like this:

cat file.txt | llm embed -m sentence-transformers/all-MiniLM-L6-v2

Or via its registered alias like this:

cat file.txt | llm embed -m all-MiniLM-L6-v2

llm-sentence-transformers <https://github.com/simonw/llm-sentence-transformers> is a complete example of a plugin that provides an embedding model.

Execute Jina embeddings with a CLI using llm-embed-jina <https://simonwillison.net/2023/Oct/26/llm-embed-jina/#how-i-built-the-plugin> talks through a similar process to add support for the Jina embeddings models <https://jina.ai/news/jina-ai-launches-worlds-first-open-source-8k-text-embedding-rivaling-openai/>​.

Embedding binary content

If your model can embed binary content, use the supports_binary property to indicate that:

class ClipEmbeddingModel(llm.EmbeddingModel):
    model_id = "clip"
    supports_binary = True
    supports_text= True

supports_text defaults to True and so is not necessary here. You can set it to False if your model only supports binary data.

If your model accepts binary, your ​.embed_batch() model may be called with a list of Python bytestrings. These may be mixed with regular strings if the model accepts both types of input.

llm-clip <https://github.com/simonw/llm-clip> is an example of a model that can embed both binary and text content.

Embedding storage format

The default output format of the llm embed command is a JSON array of floating point numbers.

LLM stores embeddings in space-efficient format: a little-endian binary sequences of 32-bit floating point numbers, each represented using 4 bytes.

These are stored in a BLOB column in a SQLite database.

The following Python functions can be used to convert between this format and an array of floating point numbers:

import struct

def encode(values):
    return struct.pack("<" + "f" * len(values), *values)

def decode(binary):
    return struct.unpack("<" + "f" * (len(binary) // 4), binary)

These functions are available as llm.encode() and llm.decode()​.

If you are using NumPy <https://numpy.org/> you can decode one of these binary values like this:

import numpy as np

numpy_array = np.frombuffer(value, "<f4")

The <f4 format string here ensures NumPy will treat the data as a little-endian sequence of 32-bit floats.

Plugins

LLM plugins can enhance LLM by making alternative Large Language Models available, either via API or by running the models locally on your machine.

Plugins can also add new commands to the llm CLI tool.

The plugin directory <#plugin-directory> lists available plugins that you can install and use.

Developing a model plugin <#tutorial-model-plugin> describes how to build a new plugin in detail.

Installing plugins

Plugins must be installed in the same virtual environment as LLM itself.

You can find names of plugins to install in the plugin directory <#plugin-directory>

Use the llm install command (a thin wrapper around pip install) to install plugins in the correct environment:

llm install llm-gpt4all

Plugins can be uninstalled with llm uninstall:

llm uninstall llm-gpt4all -y

The -y flag skips asking for confirmation.

You can see additional models that have been added by plugins by running:

llm models

Or add --options to include details of the options available for each model:

llm models --options

To run a prompt against a newly installed model, pass its name as the -m/--model option:

llm -m orca-mini-3b-gguf2-q4_0 'What is the capital of France?'

Listing installed plugins

Run llm plugins to list installed plugins:

llm plugins
[
  {
    "name": "llm-anthropic",
    "hooks": [
      "register_models"
    ],
    "version": "0.11"
  },
  {
    "name": "llm-gguf",
    "hooks": [
      "register_commands",
      "register_models"
    ],
    "version": "0.1a0"
  },
  {
    "name": "llm-clip",
    "hooks": [
      "register_commands",
      "register_embedding_models"
    ],
    "version": "0.1"
  },
  {
    "name": "llm-cmd",
    "hooks": [
      "register_commands"
    ],
    "version": "0.2a0"
  },
  {
    "name": "llm-gemini",
    "hooks": [
      "register_embedding_models",
      "register_models"
    ],
    "version": "0.3"
  }
]

Running with a subset of plugins

By default, LLM will load all plugins that are installed in the same virtual environment as LLM itself.

You can control the set of plugins that is loaded using the LLM_LOAD_PLUGINS environment variable.

Set that to the empty string to disable all plugins:

LLM_LOAD_PLUGINS='' llm ...

Or to a comma-separated list of plugin names to load only those plugins:

LLM_LOAD_PLUGINS='llm-gpt4all,llm-cluster' llm ...

You can use the llm plugins command to check that it is working correctly:

LLM_LOAD_PLUGINS='' llm plugins

Plugin directory

The following plugins are available for LLM. Here's how to install them <#installing-plugins>​.

Local models

These plugins all help you run LLMs directly on your own computer:

Remote APIs

These plugins can be used to interact with remotely hosted models via their API:

If an API model host provides an OpenAI-compatible API you can also configure LLM to talk to it <https://llm.datasette.io/en/stable/other-models.html#openai-compatible-models> without needing an extra plugin.

Tools

The following plugins add new tools <#tools> that can be used by models:

Fragments and template loaders

LLM 0.24 <#v0-24> introduced support for plugins that define -f prefix:value or -t prefix:value custom loaders for fragments and templates.

Embedding models

Embedding models <#embeddings> are models that can be used to generate and store embedding vectors for text.

Extra commands

  • llm-cmd <https://github.com/simonw/llm-cmd> accepts a prompt for a shell command, runs that prompt and populates the result in your shell so you can review it, edit it and then hit <enter> to execute or ctrl+c to cancel.
  • llm-cmd-comp <https://github.com/CGamesPlay/llm-cmd-comp> provides a key binding for your shell that will launch a chat to build the command. When ready, hit <enter> and it will go right back into your shell command line, so you can run it.
  • llm-python <https://github.com/simonw/llm-python> adds a llm python command for running a Python interpreter in the same virtual environment as LLM. This is useful for debugging, and also provides a convenient way to interact with the LLM Python API <#python-api> if you installed LLM using Homebrew or pipx​.
  • llm-cluster <https://github.com/simonw/llm-cluster> adds a llm cluster command for calculating clusters for a collection of embeddings. Calculated clusters can then be passed to a Large Language Model to generate a summary description.
  • llm-jq <https://github.com/simonw/llm-jq> lets you pipe in JSON data and a prompt describing a jq program, then executes the generated program against the JSON.

Just for fun

Plugin hooks

Plugins use plugin hooks to customize LLM's behavior. These hooks are powered by the Pluggy plugin system <https://pluggy.readthedocs.io/>​.

Each plugin can implement one or more hooks using the @hookimpl decorator against one of the hook function names described on this page.

LLM imitates the Datasette plugin system. The Datasette plugin documentation <https://docs.datasette.io/en/stable/writing_plugins.html> describes how plugins work.

register_commands(cli)

This hook adds new commands to the llm CLI tool - for example llm extra-command​.

This example plugin adds a new hello-world command that prints "Hello world!":

from llm import hookimpl
import click

@hookimpl
def register_commands(cli):
    @cli.command(name="hello-world")
    def hello_world():
        "Print hello world"
        click.echo("Hello world!")

This new command will be added to llm --help and can be run using llm hello-world​.

register_models(register, model_aliases)

This hook can be used to register one or more additional models.

import llm

@llm.hookimpl
def register_models(register):
    register(HelloWorld())

class HelloWorld(llm.Model):
    model_id = "helloworld"

    def execute(self, prompt, stream, response):
        return ["hello world"]

If your model includes an async version, you can register that too:

class AsyncHelloWorld(llm.AsyncModel):
    model_id = "helloworld"

    async def execute(self, prompt, stream, response):
        return ["hello world"]

@llm.hookimpl
def register_models(register):
    register(HelloWorld(), AsyncHelloWorld(), aliases=("hw",))

This demonstrates how to register a model with both sync and async versions, and how to specify an alias for that model.

The model_aliases parameter is a list of ModelWithAliases objects representing all models registered so far by other plugins. Plugins that use @llm.hookimpl(trylast=True) can use this to inspect or modify models registered by other plugins. Both parameters are optional - plugins can accept just register, just model_aliases, or both.

The model plugin tutorial <#tutorial-model-plugin> describes how to use this hook in detail. Asynchronous models are described here <#advanced-model-plugins-async>​.

class llm.ModelWithAliases(model: Model, async_model: AsyncModel, aliases: set[str])

A model with its optional async counterpart and aliases.

register_embedding_models(register)

This hook can be used to register one or more additional embedding models, as described in Writing plugins to add new embedding models <#embeddings-writing-plugins>​.

import llm

@llm.hookimpl
def register_embedding_models(register):
    register(HelloWorld())

class HelloWorld(llm.EmbeddingModel):
    model_id = "helloworld"

    def embed_batch(self, items):
        return [[1, 2, 3], [4, 5, 6]]

register_tools(register)

This hook can register one or more tool functions for use with LLM. See the tools documentation <#tools> for more details.

This example registers two tools: upper and count_character_in_word​.

import llm

def upper(text: str) -> str:
    """Convert text to uppercase."""
    return text.upper()

def count_char(text: str, character: str) -> int:
    """Count the number of occurrences of a character in a word."""
    return text.count(character)

@llm.hookimpl
def register_tools(register):
    register(upper)
    # Here the name= argument is used to specify a different name for the tool:
    register(count_char, name="count_character_in_word")

Tools can also be implemented as classes, as described in Toolbox classes <#python-api-toolbox> in the Python API documentation.

You can register classes like the Memory example from here <#python-api-toolbox> by passing the class (not an instance of the class) to register():

import llm

class Memory(llm.Toolbox):
    # Copy implementation from the Python API documentation

@llm.hookimpl
def register_tools(register):
    register(Memory)

Once installed, this tool can be used like so:

llm chat -T Memory

If a tool name starts with a capital letter it is assumed to be a toolbox class, not a regular tool function.

Here's an example session with the Memory tool:

Chatting with gpt-4.1-mini
Type 'exit' or 'quit' to exit
Type '!multi' to enter multiple lines, then '!end' to finish
Type '!edit' to open your default editor and modify the prompt
Type '!fragment <my_fragment> [<another_fragment> ...]' to insert one or more fragments
> Remember my name is Henry

Tool call: Memory_set({'key': 'user_name', 'value': 'Henry'})
  null

Got it, Henry! I'll remember your name. How can I assist you today?
> what keys are there?

Tool call: Memory_keys({})
  [
    "user_name"
  ]

Currently, there is one key stored: "user_name". Would you like to add or retrieve any information?
> read it

Tool call: Memory_get({'key': 'user_name'})
  Henry

The value stored under the key "user_name" is Henry. Is there anything else you'd like to do?
> add Barrett to it

Tool call: Memory_append({'key': 'user_name', 'value': 'Barrett'})
  null

I have added "Barrett" to the key "user_name". If you want, I can now show you the updated value.
> show value

Tool call: Memory_get({'key': 'user_name'})
  Henry
  Barrett

The value stored under the key "user_name" is now:
Henry
Barrett

Is there anything else you would like to do?

register_template_loaders(register)

Plugins can register new template loaders <#prompt-templates-loaders> using the register_template_loaders hook.

Template loaders work with the llm -t prefix:name syntax. The prefix specifies the loader, then the registered loader function is called with the name as an argument. The loader function should return an llm.Template() object.

This example plugin registers my-prefix as a new template loader. Once installed it can be used like this:

llm -t my-prefix:my-template

Here's the Python code:

import llm

@llm.hookimpl
def register_template_loaders(register):
    register("my-prefix", my_template_loader)

def my_template_loader(template_path: str) -> llm.Template:
    """
    Documentation for the template loader goes here. It will be displayed
    when users run the 'llm templates loaders' command.
    """
    try:
        # Your logic to fetch the template content
        # This is just an example:
        prompt = "This is a sample prompt for {}".format(template_path)
        system = "You are an assistant specialized in {}".format(template_path)

        # Return a Template object with the required fields
        return llm.Template(
            name=template_path,
            prompt=prompt,
            system=system,
        )
    except Exception as e:
        # Raise a ValueError with a clear message if the template cannot be found
        raise ValueError(f"Template '{template_path}' could not be loaded: {str(e)}")

The llm.Template class has the following constructor:

class llm.Template(*, name: str, prompt: str | None = None, system: str | None = None, attachments: list[str] | None = None, attachment_types: list[AttachmentType] | None = None, model: str | None = None, defaults: dict[str, Any] | None = None, options: dict[str, Any] | None = None, extract: bool | None = None, extract_last: bool | None = None, schema_object: dict | None = None, fragments: list[str] | None = None, system_fragments: list[str] | None = None, tools: list[str] | None = None, functions: str | None = None)

A reusable prompt template.

The loader function should raise a ValueError if the template cannot be found or loaded correctly, providing a clear error message. If you need to translate an exception from another library, catch that specific exception and use raise ValueError(...) from ex to preserve its context.

Note that functions: provided by templates using this plugin hook will not be made available, to avoid the risk of plugin hooks that load templates from remote sources introducing arbitrary code execution vulnerabilities.

register_fragment_loaders(register)

Plugins can register new fragment loaders using the register_fragment_loaders hook. These can then be used with the llm -f prefix:argument syntax.

Fragment loader plugins differ from template loader plugins in that you can stack more than one fragment loader call together in the same prompt.

A fragment loader can return one or more string fragments or attachments, or a mixture of the two. The fragments will be concatenated together into the prompt string, while any attachments will be added to the list of attachments to be sent to the model.

The prefix specifies the loader. The argument will be passed to that registered callback..

The callback works in a very similar way to template loaders, but returns either a single llm.Fragment, a list of llm.Fragment objects, a single llm.Attachment, or a list that can mix llm.Attachment and llm.Fragment objects.

The llm.Fragment constructor takes a required string argument (the content of the fragment) and an optional second source argument, which is a string that may be displayed as debug information. For files this is a path and for URLs it is a URL. Your plugin can use anything you like for the source value.

See the Python API documentation for attachments <#python-api-attachments> for details of the llm.Attachment class.

Here is some example code:

import llm

@llm.hookimpl
def register_fragment_loaders(register):
    register("my-fragments", my_fragment_loader)


def my_fragment_loader(argument: str) -> llm.Fragment:
    """
    Documentation for the fragment loader goes here. It will be displayed
    when users run the 'llm fragments loaders' command.
    """
    try:
        fragment = "Fragment content for {}".format(argument)
        source = "my-fragments:{}".format(argument)
        return llm.Fragment(fragment, source)
    except Exception as ex:
        # Raise a ValueError with a clear message if the fragment cannot be loaded
        raise ValueError(
            f"Fragment 'my-fragments:{argument}' could not be loaded: {str(ex)}"
        )

# Or for the case where you want to return multiple fragments and attachments:
def my_fragment_loader(
    argument: str,
) -> list[llm.Fragment | llm.Attachment]:
    "Docs go here."
    return [
        llm.Fragment("Fragment 1 content", f"my-fragments:{argument}"),
        llm.Fragment("Fragment 2 content", f"my-fragments:{argument}"),
        llm.Attachment(path="/path/to/image.png"),
    ]

A plugin like this one can be called like so:

llm -f my-fragments:argument

If multiple fragments are returned they will be used as if the user passed multiple -f X arguments to the command.

Multiple fragments are particularly useful for things like plugins that return every file in a directory. If these were concatenated together by the plugin, a change to a single file would invalidate the de-duplication cache for that whole fragment. Giving each file its own fragment means we can avoid storing multiple copies of that full collection if only a single file has changed.

Developing a model plugin

This tutorial will walk you through developing a new plugin for LLM that adds support for a new Large Language Model.

We will be developing a plugin that implements a simple Markov chain <https://en.wikipedia.org/wiki/Markov_chain> to generate words based on an input string. Markov chains are not technically large language models, but they provide a useful exercise for demonstrating how the LLM tool can be extended through plugins.

The initial structure of the plugin

First create a new directory with the name of your plugin - it should be called something like llm-markov​.

mkdir llm-markov
cd llm-markov

In that directory create a file called llm_markov.py containing this:

import llm

@llm.hookimpl
def register_models(register):
    register(Markov())

class Markov(llm.Model):
    model_id = "markov"

    def execute(self, prompt, stream, response, conversation):
        return ["hello world"]

The def register_models() function here is called by the plugin system (thanks to the @hookimpl decorator). It uses the register() function passed to it to register an instance of the new model.

The Markov class implements the model. It sets a model_id - an identifier that can be passed to llm -m in order to identify the model to be executed.

The logic for executing the model goes in the execute() method. We'll extend this to do something more useful in a later step.

Next, create a pyproject.toml file. This is necessary to tell LLM how to load your plugin:

[project]
name = "llm-markov"
version = "0.1"

[project.entry-points.llm]
markov = "llm_markov"

This is the simplest possible configuration. It defines a plugin name and provides an entry point <https://setuptools.pypa.io/en/latest/userguide/entry_point.html> for llm telling it how to load the plugin.

If you are comfortable with Python virtual environments you can create one now for your project, activate it and run pip install llm before the next step.

If you aren't familiar with virtual environments, don't worry: you can develop plugins without them. You'll need to have LLM installed using Homebrew or pipx or one of the other installation options <https://llm.datasette.io/en/latest/setup.html#installation>​.

Installing your plugin to try it out

Having created a directory with a pyproject.toml file and an llm_markov.py file, you can install your plugin into LLM by running this from inside your llm-markov directory:

llm install -e .

The -e stands for "editable" - it means you'll be able to make further changes to the llm_markov.py file that will be reflected without you having to reinstall the plugin.

The ​. means the current directory. You can also install editable plugins by passing a path to their directory this:

llm install -e path/to/llm-markov

To confirm that your plugin has installed correctly, run this command:

llm plugins

The output should look like this:

[
  {
    "name": "llm-markov",
    "hooks": [
      "register_models"
    ],
    "version": "0.1"
  },
  {
    "name": "llm.default_plugins.openai_models",
    "hooks": [
      "register_commands",
      "register_models"
    ]
  }
]

This command lists default plugins that are included with LLM as well as new plugins that have been installed.

Now let's try the plugin by running a prompt through it:

llm -m markov "the cat sat on the mat"

It outputs:

hello world

Next, we'll make it execute and return the results of a Markov chain.

Building the Markov chain

Markov chains can be thought of as the simplest possible example of a generative language model. They work by building an index of words that have been seen following other words.

Here's what that index looks like for the phrase "the cat sat on the mat"

{
  "the": ["cat", "mat"],
  "cat": ["sat"],
  "sat": ["on"],
  "on": ["the"]
}

Here's a Python function that builds that data structure from a text input:

def build_markov_table(text):
    words = text.split()
    transitions = {}
    # Loop through all but the last word
    for i in range(len(words) - 1):
        word = words[i]
        next_word = words[i + 1]
        transitions.setdefault(word, []).append(next_word)
    return transitions

We can try that out by pasting it into the interactive Python interpreter and running this:

>>> transitions = build_markov_table("the cat sat on the mat")
>>> transitions
{'the': ['cat', 'mat'], 'cat': ['sat'], 'sat': ['on'], 'on': ['the']}

Executing the Markov chain

To execute the model, we start with a word. We look at the options for words that might come next and pick one of those at random. Then we repeat that process until we have produced the desired number of output words.

Some words might not have any following words from our training sentence. For our implementation we will fall back on picking a random word from our collection.

We will implement this as a Python generator <https://realpython.com/introduction-to-python-generators/>, using the yield keyword to produce each token:

def generate(transitions, length, start_word=None):
    all_words = list(transitions.keys())
    next_word = start_word or random.choice(all_words)
    for i in range(length):
        yield next_word
        options = transitions.get(next_word) or all_words
        next_word = random.choice(options)

If you aren't familiar with generators, the above code could also be implemented like this - creating a Python list and returning it at the end of the function:

def generate_list(transitions, length, start_word=None):
    all_words = list(transitions.keys())
    next_word = start_word or random.choice(all_words)
    output = []
    for i in range(length):
        output.append(next_word)
        options = transitions.get(next_word) or all_words
        next_word = random.choice(options)
    return output

You can try out the generate() function like this:

lookup = build_markov_table("the cat sat on the mat")
for word in generate(transitions, 20):
    print(word)

Or you can generate a full string sentence with it like this:

sentence = " ".join(generate(transitions, 20))

Adding that to the plugin

Our execute() method from earlier currently returns the list ["hello world"]​.

Update that to use our new Markov chain generator instead. Here's the full text of the new llm_markov.py file:

import llm
import random

@llm.hookimpl
def register_models(register):
    register(Markov())

def build_markov_table(text):
    words = text.split()
    transitions = {}
    # Loop through all but the last word
    for i in range(len(words) - 1):
        word = words[i]
        next_word = words[i + 1]
        transitions.setdefault(word, []).append(next_word)
    return transitions

def generate(transitions, length, start_word=None):
    all_words = list(transitions.keys())
    next_word = start_word or random.choice(all_words)
    for i in range(length):
        yield next_word
        options = transitions.get(next_word) or all_words
        next_word = random.choice(options)

class Markov(llm.Model):
    model_id = "markov"

    def execute(self, prompt, stream, response, conversation):
        text = prompt.prompt
        transitions = build_markov_table(text)
        for word in generate(transitions, 20):
            yield word + ' '

The execute() method can access the text prompt that the user provided using prompt.prompt - prompt is a Prompt object that might include other more advanced input details as well.

Now when you run this you should see the output of the Markov chain!

llm -m markov "the cat sat on the mat"
the mat the cat sat on the cat sat on the mat cat sat on the mat cat sat on

Understanding execute()

The full signature of the execute() method is:

def execute(self, prompt, stream, response, conversation):

The prompt argument is a Prompt object that contains the text that the user provided, the system prompt and the provided options.

stream is a boolean that says if the model is being run in streaming mode.

response is the Response object that is being created by the model. This is provided so you can write additional information to response.response_json, which may be logged to the database.

conversation is the Conversation that the prompt is a part of - or None if no conversation was provided. Some models may use conversation.responses to access previous prompts and responses in the conversation and use them to construct a call to the LLM that includes previous context.

Prompts and responses are logged to the database

The prompt and the response will be logged to a SQLite database automatically by LLM. You can see the single most recent addition to the logs using:

llm logs -n 1

The output should look something like this:

[
  {
    "id": "01h52s4yez2bd1qk2deq49wk8h",
    "model": "markov",
    "prompt": "the cat sat on the mat",
    "system": null,
    "prompt_json": null,
    "options_json": {},
    "response": "on the cat sat on the cat sat on the mat cat sat on the cat sat on the cat ",
    "response_json": null,
    "conversation_id": "01h52s4yey7zc5rjmczy3ft75g",
    "duration_ms": 0,
    "datetime_utc": "2023-07-11T15:29:34.685868",
    "conversation_name": "the cat sat on the mat",
    "conversation_model": "markov"
  }
]

Plugins can log additional information to the database by assigning a dictionary to the response.response_json property during the execute() method.

Here's how to include that full transitions table in the response_json in the log:

    def execute(self, prompt, stream, response, conversation):
        text = self.prompt.prompt
        transitions = build_markov_table(text)
        for word in generate(transitions, 20):
            yield word + ' '
        response.response_json = {"transitions": transitions}

Now when you run the logs command you'll see that too:

llm logs -n 1
[
  {
    "id": 623,
    "model": "markov",
    "prompt": "the cat sat on the mat",
    "system": null,
    "prompt_json": null,
    "options_json": {},
    "response": "on the mat the cat sat on the cat sat on the mat sat on the cat sat on the ",
    "response_json": {
      "transitions": {
        "the": [
          "cat",
          "mat"
        ],
        "cat": [
          "sat"
        ],
        "sat": [
          "on"
        ],
        "on": [
          "the"
        ]
      }
    },
    "reply_to_id": null,
    "chat_id": null,
    "duration_ms": 0,
    "datetime_utc": "2023-07-06T01:34:45.376637"
  }
]

In this particular case this isn't a great idea here though: the transitions table is duplicate information, since it can be reproduced from the input data - and it can get really large for longer prompts.

Adding options

LLM models can take options. For large language models these can be things like temperature or top_k​.

Options are passed using the -o/--option command line parameters, for example:

llm -m gpt4 "ten pet pelican names" -o temperature 1.5

We're going to add two options to our Markov chain model:

  • length: Number of words to generate
  • delay: a floating point number of Delay in between output token

The delay token will let us simulate a streaming language model, where tokens take time to generate and are returned by the execute() function as they become ready.

Options are defined using an inner class on the model, called Options​. It should extend the llm.Options class.

Add this Options class to your model:

class Markov(Model):
    model_id = "markov"

    class Options(llm.Options):
        length: int | None = None
        delay: float | None = None

Let's add extra validation rules to our options. Length must be at least 2. Duration must be between 0 and 10.

The Options class uses Pydantic 2 <https://pydantic.dev/>, which can support all sorts of advanced validation rules.

We can also add inline documentation, which can then be displayed by the llm models --options command.

Add these imports to the top of llm_markov.py:

from pydantic import field_validator, Field

We can now add Pydantic field validators for our two new rules, plus inline documentation:

    class Options(llm.Options):
        length: int | None = Field(
            description="Number of words to generate",
            default=None
        )
        delay: float | None = Field(
            description="Seconds to delay between each token",
            default=None
        )

        @field_validator("length")
        def validate_length(cls, length):
            if length is None:
                return None
            if length < 2:
                raise ValueError("length must be >= 2")
            return length

        @field_validator("delay")
        def validate_delay(cls, delay):
            if delay is None:
                return None
            if not 0 <= delay <= 10:
                raise ValueError("delay must be between 0 and 10")
            return delay

Lets test our options validation:

llm -m markov "the cat sat on the mat" -o length -1
Error: length
  Value error, length must be >= 2

Next, we will modify our execute() method to handle those options. Add this to the beginning of llm_markov.py:

import time

Then replace the execute() method with this one:

    def execute(self, prompt, stream, response, conversation):
        text = prompt.prompt
        transitions = build_markov_table(text)
        length = prompt.options.length or 20
        for word in generate(transitions, length):
            yield word + ' '
            if prompt.options.delay:
                time.sleep(prompt.options.delay)

Add can_stream = True to the top of the Markov model class, on the line below `model_id = "markov". This tells LLM that the model is able to stream content to the console.

The full llm_markov.py file should now look like this:

import random
import time

from pydantic import Field, field_validator

import llm


@llm.hookimpl
def register_models(register):
    register(Markov())


def build_markov_table(text):
    words = text.split()
    transitions = {}
    # Loop through all but the last word
    for i in range(len(words) - 1):
        word = words[i]
        next_word = words[i + 1]
        transitions.setdefault(word, []).append(next_word)
    return transitions


def generate(transitions, length, start_word=None):
    all_words = list(transitions.keys())
    next_word = start_word or random.choice(all_words)
    for i in range(length):
        yield next_word
        options = transitions.get(next_word) or all_words
        next_word = random.choice(options)


class Markov(llm.Model):
    model_id = "markov"
    can_stream = True

    class Options(llm.Options):
        length: int | None = Field(
            description="Number of words to generate", default=None
        )
        delay: float | None = Field(
            description="Seconds to delay between each token", default=None
        )

        @field_validator("length")
        def validate_length(cls, length):
            if length is None:
                return None
            if length < 2:
                raise ValueError("length must be >= 2")
            return length

        @field_validator("delay")
        def validate_delay(cls, delay):
            if delay is None:
                return None
            if not 0 <= delay <= 10:
                raise ValueError("delay must be between 0 and 10")
            return delay

    def execute(self, prompt, stream, response, conversation):
        text = prompt.prompt
        transitions = build_markov_table(text)
        length = prompt.options.length or 20
        for word in generate(transitions, length):
            yield word + " "
            if prompt.options.delay:
                time.sleep(prompt.options.delay)

Now we can request a 20 word completion with a 0.1s delay between tokens like this:

llm -m markov "the cat sat on the mat" \
  -o length 20 -o delay 0.1

LLM provides a --no-stream option users can use to turn off streaming. Using that option causes LLM to gather the response from the stream and then return it to the console in one block. You can try that like this:

llm -m markov "the cat sat on the mat" \
  -o length 20 -o delay 0.1 --no-stream

In this case it will still delay for 2s total while it gathers the tokens, then output them all at once.

That --no-stream option causes the stream argument passed to execute() to be false. Your execute() method can then behave differently depending on whether it is streaming or not.

Options are also logged to the database. You can see those here:

llm logs -n 1
[
  {
    "id": 636,
    "model": "markov",
    "prompt": "the cat sat on the mat",
    "system": null,
    "prompt_json": null,
    "options_json": {
      "length": 20,
      "delay": 0.1
    },
    "response": "the mat on the mat on the cat sat on the mat sat on the mat cat sat on the ",
    "response_json": null,
    "reply_to_id": null,
    "chat_id": null,
    "duration_ms": 2063,
    "datetime_utc": "2023-07-07T03:02:28.232970"
  }
]

Distributing your plugin

There are many different options for distributing your new plugin so other people can try it out.

You can create a downloadable wheel or ​.zip or ​.tar.gz files, or share the plugin through GitHub Gists or repositories.

You can also publish your plugin to PyPI, the Python Package Index.

Wheels and sdist packages

The easiest option is to produce a distributable package is to use the build command. First, install the build package by running this:

python -m pip install build

Then run build in your plugin directory to create the packages:

python -m build

This will create two files: dist/llm-markov-0.1.tar.gz and dist/llm-markov-0.1-py3-none-any.whl​.

Either of these files can be used to install the plugin:

llm install dist/llm_markov-0.1-py3-none-any.whl

If you host this file somewhere online other people will be able to install it using pip install against the URL to your package:

llm install 'https://.../llm_markov-0.1-py3-none-any.whl'

You can run the following command at any time to uninstall your plugin, which is useful for testing out different installation methods:

llm uninstall llm-markov -y

GitHub Gists

A neat quick option for distributing a simple plugin is to host it in a GitHub Gist. These are available for free with a GitHub account, and can be public or private. Gists can contain multiple files but don't support directory structures - which is OK, because our plugin is just two files, pyproject.toml and llm_markov.py​.

Here's an example Gist I created for this tutorial:

<https://gist.github.com/simonw/6e56d48dc2599bffba963cef0db27b6d>

You can turn a Gist into an installable ​.zip URL by right-clicking on the "Download ZIP" button and selecting "Copy Link". Here's that link for my example Gist:

https://gist.github.com/simonw/6e56d48dc2599bffba963cef0db27b6d/archive/cc50c854414cb4deab3e3ab17e7e1e07d45cba0c.zip

The plugin can be installed using the llm install command like this:

llm install 'https://gist.github.com/simonw/6e56d48dc2599bffba963cef0db27b6d/archive/cc50c854414cb4deab3e3ab17e7e1e07d45cba0c.zip'

GitHub repositories

The same trick works for regular GitHub repositories as well: the "Download ZIP" button can be found by clicking the green "Code" button at the top of the repository. The URL which that provides can then be used to install the plugin that lives in that repository.

Publishing plugins to PyPI

The Python Package Index (PyPI) <https://pypi.org/> is the official repository for Python packages. You can upload your plugin to PyPI and reserve a name for it - once you have done that, anyone will be able to install your plugin using llm install <name>​.

Follow these instructions <https://packaging.python.org/en/latest/tutorials/packaging-projects/#uploading-the-distribution-archives> to publish a package to PyPI. The short version:

python -m pip install twine
python -m twine upload dist/*

You will need an account on PyPI, then you can enter your username and password - or create a token in the PyPI settings and use __token__ as the username and the token as the password.

Adding metadata

Before uploading a package to PyPI it's a good idea to add documentation and expand pyproject.toml with additional metadata.

Create a README.md file in the root of your plugin directory with instructions about how to install, configure and use your plugin.

You can then replace pyproject.toml with something like this:

[project]
name = "llm-markov"
version = "0.1"
description = "Plugin for LLM adding a Markov chain generating model"
readme = "README.md"
authors = [{name = "Simon Willison"}]
license = {text = "Apache-2.0"}
classifiers = [
    "License :: OSI Approved :: Apache Software License"
]
dependencies = [
    "llm"
]
requires-python = ">3.7"

[project.urls]
Homepage = "https://github.com/simonw/llm-markov"
Changelog = "https://github.com/simonw/llm-markov/releases"
Issues = "https://github.com/simonw/llm-markov/issues"

[project.entry-points.llm]
markov = "llm_markov"

This will pull in your README to be displayed as part of your project's listing page on PyPI.

It adds llm as a dependency, ensuring it will be installed if someone tries to install your plugin package without it.

It adds some links to useful pages (you can drop the project.urls section if those links are not useful for your project).

You should drop a LICENSE file into the GitHub repository for your package as well. I like to use the Apache 2 license like this <https://github.com/simonw/llm/blob/main/LICENSE>​.

What to do if it breaks

Sometimes you may make a change to your plugin that causes it to break, preventing llm from starting. For example you may see an error like this one:

$ llm 'hi'
Traceback (most recent call last):
  ...
  File llm-markov/llm_markov.py", line 10
    register(Markov()):
                      ^
SyntaxError: invalid syntax

You may find that you are unable to uninstall the plugin using llm uninstall llm-markov because the command itself fails with the same error.

Should this happen, you can uninstall the plugin after first disabling it using the LLM_LOAD_PLUGINS <#llm-load-plugins> environment variable like this:

LLM_LOAD_PLUGINS='' llm uninstall llm-markov

Advanced model plugins

The model plugin tutorial <#tutorial-model-plugin> covers the basics of developing a plugin that adds support for a new model. This document covers more advanced topics.

Features to consider for your model plugin include:

  • Accepting API keys using the standard mechanism that incorporates llm keys set, environment variables and support for passing an explicit key to the model.
  • Including support for Async models that can be used with Python's asyncio library.
  • Support for structured output using JSON schemas.
  • Support for tools​.
  • Handling attachments (images, audio and more) for multi-modal models.
  • Tracking token usage for models that charge by the token.

Tip: lazily load expensive dependencies

If your plugin depends on an expensive library such as PyTorch <https://pytorch.org/> you should avoid importing that dependency (or a dependency that uses that dependency) at the top level of your module. Expensive imports in plugins mean that even simple commands like llm --help can take a long time to run.

Instead, move those imports to inside the methods that need them. Here's an example change to llm-sentence-transformers <https://github.com/simonw/llm-sentence-transformers/commit/f87df71e8a652a8cb05ad3836a79b815bcbfa64b> that shaved 1.8 seconds off the time it took to run llm --help!

Models that accept API keys

Models that call out to API providers such as OpenAI, Anthropic or Google Gemini usually require an API key.

LLM's API key management mechanism is described here <#api-keys>​.

If your plugin requires an API key you should subclass the llm.KeyModel class instead of the llm.Model class. Start your model definition like this:

import llm

class HostedModel(llm.KeyModel):
    needs_key = "hosted" # Required
    key_env_var = "HOSTED_API_KEY" # Optional

This tells LLM that your model requires an API key, which may be saved in the key registry under the key name hosted or might also be provided as the HOSTED_API_KEY environment variable.

Then when you define your execute() method it should take an extra key= parameter like this:

    def execute(self, prompt, stream, response, conversation, key=None):
        # key= here will be the API key to use

LLM will pass in the key from the environment variable, key registry or that has been passed to LLM as the --key command-line option or the model.prompt(..., key=) parameter.

Async models

Plugins can optionally provide an asynchronous version of their model, suitable for use with Python asyncio <https://docs.python.org/3/library/asyncio.html>​. This is particularly useful for remote models accessible by an HTTP API.

The async version of a model subclasses llm.AsyncModel instead of llm.Model​. It must implement an async def execute() async generator method instead of def execute()​.

This example shows a subset of the OpenAI default plugin illustrating how this method might work:

from collections.abc import AsyncGenerator

import llm

class MyAsyncModel(llm.AsyncModel):
    # This can duplicate the model_id of the sync model:
    model_id = "my-model-id"

    async def execute(
        self, prompt, stream, response, conversation=None
    ) -> AsyncGenerator[str, None]:
        if stream:
            completion = await client.chat.completions.create(
                model=self.model_id,
                messages=messages,
                stream=True,
            )
            async for chunk in completion:
                yield chunk.choices[0].delta.content
        else:
            completion = await client.chat.completions.create(
                model=self.model_name or self.model_id,
                messages=messages,
                stream=False,
            )
            if completion.choices[0].message.content is not None:
                yield completion.choices[0].message.content

If your model takes an API key you should instead subclass llm.AsyncKeyModel and have a key= parameter on your ​.execute() method:

class MyAsyncModel(llm.AsyncKeyModel):
    ...
    async def execute(
        self, prompt, stream, response, conversation=None, key=None
    ) -> AsyncGenerator[str, None]:

This async model instance should then be passed to the register() method in the register_models() plugin hook:

@hookimpl
def register_models(register):
    register(
        MyModel(), MyAsyncModel(), aliases=("my-model-aliases",)
    )

The prompt object passed to your execute() method is an instance of Prompt:

class llm.Prompt(prompt, model, *, fragments=None, attachments=None, system=None, system_fragments=None, prompt_json=None, options=None, schema=None, tools=None, tool_results=None, messages=None, hide_reasoning=False)

The prompt being sent to the model.

property prompt

The text of the prompt, with any fragments concatenated.

property system

The system prompt, with any system fragments concatenated.

Supporting schemas

If your model supports structured output <#schemas> against a defined JSON schema you can implement support by first adding supports_schema = True to the class:

class MyModel(llm.KeyModel):
    ...
    support_schema = True

And then adding code to your ​.execute() method that checks for prompt.schema and, if it is present, uses that to prompt the model.

prompt.schema will always be a Python dictionary representing a JSON schema, even if the user passed in a Pydantic model class.

Check the llm-gemini <https://github.com/simonw/llm-gemini> and llm-anthropic <https://github.com/simonw/llm-anthropic> plugins for example of this pattern in action.

Supporting tools

Adding tools support <#tools> involves several steps:

  1. Add supports_tools = True to your model class.
  2. If prompt.tools is populated, turn that list of llm.Tool objects into the correct format for your model.
  3. Look out for requests to call tools in the responses from your model. Call response.add_tool_call(llm.ToolCall(...)) for each of those. This should work for streaming and non-streaming and async and non-async cases. Pass the provider's tool call ID as tool_call_id= if there is one; if you omit it LLM synthesizes a unique tc_-prefixed id, since consumers rely on every tool call having one.
  4. If your prompt has a prompt.tool_results list, pass the information from those llm.ToolResult objects to your model.
  5. Include prompt.tools and prompt.tool_results and tool calls from response.tool_calls_or_raise() in the conversation history constructed by your plugin.
  6. Make sure your code is OK with prompts that do not have prompt.prompt set to a value, since they may be carrying exclusively the results of a tool call.

This commit to llm-gemini <https://github.com/simonw/llm-gemini/commit/a7f1096cfbb733018eb41c29028a8cc6160be298> implementing tools helps demonstrate what this looks like for a real plugin.

Here are the relevant dataclasses:

class llm.Tool(name: str, description: str | None = None, input_schema: dict = <factory>, implementation: Callable | None = None, plugin: str | None = None)

A tool that can be called by a model.

class llm.ToolCall(name: str, arguments: dict, tool_call_id: str | None = None)

A request by the model to call a tool.

class llm.ToolResult(name: str, output: str, attachments: list[Attachment <#llm.Attachment>] = <factory>, tool_call_id: str | None = None, instance: Toolbox <#llm.Toolbox> | None = None, exception: Exception | None = None)

The result of executing a tool call.

Supporting server-side tools

Server-side tools execute inside the provider's infrastructure rather than in LLM's local tool loop. Provider plugins represent these by subclassing llm.ServerSideTool:

class ProviderSearch(llm.ServerSideTool):
    "A search tool executed by Example Provider."

    name = "provider_search"

    def __init__(self, allowed_domains=None):
        self.allowed_domains = allowed_domains

    def tool_spec(self, model):
        spec = {"type": "provider_search"}
        if self.allowed_domains:
            spec["allowed_domains"] = self.allowed_domains
        return spec

    def prepare_request(self, model, kwargs):
        # Add any other request fields this tool requires. Merge with existing values instead of replacing them.
        include = kwargs.setdefault("include", [])
        if "provider_search.results" not in include:
            include.append("provider_search.results")

Model instances expose the server-side tool classes they support using the supported_server_side_tools property:

class MyModel(llm.KeyModel):
    @property
    def supported_server_side_tools(self):
        return (ProviderSearch,)

This property is evaluated on the model instance, so it can use self.model_id or other instance configuration to vary the available tools. It is independent of supports_tools: that flag describes locally executed function tools. A model can support server-side tools, function tools, both or neither.

prompt.tools can contain both llm.Tool and llm.ServerSideTool instances. The adapter should partition that list, put each server-side tool's tool_spec(model) result wherever its provider expects it and, after the baseline request is complete, call tool.prepare_request(model, kwargs) once for each server-side tool in list order. LLM validates the model declaration before execute() runs, but it does not interpret the specification or call either method itself.

Providers with an OpenAI-compatible tools array can optionally support raw specifications by including llm.ServerSideTool in this property. This claims direct instances such as:

llm.ServerSideTool({"type": "browser_search"})

Server-side tool calls returned by the provider should use the server_executed=True events described in Structured messages and streaming events​.

class llm.ServerSideTool(spec: dict | None = None)

A tool executed inside the provider's infrastructure.

Instances are passed in tools=[...] alongside function tools. The framework transports and validates them but never executes them. Provider plugins subclass this class for their own tools; the base class can be instantiated directly with a raw provider tool specification.

prepare_request(model, kwargs: dict) -> None

Add any other values this tool needs to provider request kwargs.

tool_spec(model) -> dict

Return this tool's provider-specific request specification.

Attachments for multi-modal models

Models such as GPT-4o, Claude 3.5 Sonnet and Google's gemini-flash-latest are multi-modal: they accept input in the form of images and maybe even audio, video and other formats.

LLM calls these attachments​. Models can specify the types of attachments they accept and then implement special code in the ​.execute() method to handle them.

See the Python attachments documentation <#python-api-attachments> for details on using attachments in the Python API.

Specifying attachment types

A Model subclass can list the types of attachments it accepts by defining an attachment_types class attribute:

class NewModel(llm.Model):
    model_id = "new-model"
    attachment_types = frozenset(
        {
            "image/png",
            "image/jpeg",
            "image/webp",
            "image/gif",
        }
    )

These content types are detected when an attachment is passed to LLM using llm -a filename, or can be specified by the user using the --attachment-type filename image/png option.

Note: MP3 files will have their attachment type detected as audio/mpeg, not audio/mp3​.

LLM will use the attachment_types attribute to validate that provided attachments should be accepted before passing them to the model.

Handling attachments

The prompt object passed to the execute() method will have an attachments attribute containing a list of Attachment objects provided by the user.

An Attachment instance has the following properties:

  • url (str): The URL of the attachment, if it was provided as a URL
  • path (str): The resolved file path of the attachment, if it was provided as a file
  • type (str): The content type of the attachment, if it was provided
  • content (bytes): The binary content of the attachment, if it was provided

Generally only one of url, path or content will be set.

You should usually access the type and the content through one of these methods:

  • attachment.resolve_type() -> str: Returns the type if it is available, otherwise attempts to guess the type by looking at the first few bytes of content
  • attachment.content_bytes() -> bytes: Returns the binary content, which it may need to read from a file or fetch from a URL
  • attachment.base64_content() -> str: Returns that content as a base64-encoded string

A id() method returns a database ID for this content, which is either a SHA256 hash of the binary content or, in the case of attachments hosted at an external URL, a hash of {"url": url} instead. This is an implementation detail which you should not need to access directly.

Note that it's possible for a prompt with an attachments to not include a text prompt at all, in which case prompt.prompt will be None​.

Here's how the OpenAI plugin handles attachments, including the case where no prompt.prompt was provided:

if not prompt.attachments:
    messages.append({"role": "user", "content": prompt.prompt})
else:
    attachment_message = []
    if prompt.prompt:
        attachment_message.append({"type": "text", "text": prompt.prompt})
    for attachment in prompt.attachments:
        attachment_message.append(_attachment(attachment))
    messages.append({"role": "user", "content": attachment_message})


# And the code for creating the attachment message
def _attachment(attachment):
    url = attachment.url
    base64_content = ""
    if not url or attachment.resolve_type().startswith("audio/"):
        base64_content = attachment.base64_content()
        url = f"data:{attachment.resolve_type()};base64,{base64_content}"
    if attachment.resolve_type().startswith("image/"):
        return {"type": "image_url", "image_url": {"url": url}}
    else:
        format_ = "wav" if attachment.resolve_type() == "audio/wav" else "mp3"
        return {
            "type": "input_audio",
            "input_audio": {
                "data": base64_content,
                "format": format_,
            },
        }

As you can see, it uses attachment.url if that is available and otherwise falls back to using the base64_content() method to embed the image directly in the JSON sent to the API. For the OpenAI API audio attachments are always included as base64-encoded strings.

Attachments from previous conversations

Conversation history — including attachments from prior turns — is available on the canonical prompt.messages list. See the next section for how that works.

Structured messages and streaming events

The 0.32 alpha introduced a richer contract for plugins than "yield strings":

  1. execute() yields StreamEvent objects (or plain str, still supported) so text, reasoning (thinking tokens), tool calls, and server-side tool results each surface as their own event type. The framework assembles these into typed Part objects.
  2. build_messages (or equivalent) reads prompt.messages — a list[llm.Message] that is the complete input chain for this turn.
  3. Opaque provider tokens round-trip via provider_metadata — Anthropic thinking signatures, Gemini thought signatures, OpenAI Responses API encrypted reasoning blobs. Plugins stash whatever the API returns, then echo it back on the next request.

Older plugins still work. A plugin that still yields plain str from execute() works unchanged — each string is wrapped as a StreamEvent(type="text", chunk=...) internally.

Yielding StreamEvent from execute()

from llm.parts import StreamEvent

def execute(self, prompt, stream, response, conversation, key=None):
    messages = self.build_messages(prompt, conversation)
    ...

    for chunk in provider_sdk.stream(...):
        if chunk.type == "text":
            yield StreamEvent(type="text", chunk=chunk.text)
        elif chunk.type == "thinking":
            yield StreamEvent(type="reasoning", chunk=chunk.text)

A StreamEvent has four frequently-used fields:

  • type — one of "text", "reasoning", "tool_call_name", "tool_call_args", "tool_result"​.
  • chunk — the text fragment. For tool calls this is the tool name (for tool_call_name) or a partial JSON string (for tool_call_args).
  • tool_call_id — the provider's id for the tool call, set on tool_call_name / tool_call_args / tool_result events. Also the signal the framework uses to group tool-call events into one ToolCallPart​.
  • provider_metadata — an optional dict[str, dict] namespaced by provider name. Carries opaque data (signatures, encrypted blobs) that must be echoed back on future requests.

Three additional fields exist for special cases:

  • server_executed: bool — set True for server-side tool calls (for example, Anthropic web search) and their results. This means the model ran the tool internally as part of responding to the prompt.
  • tool_name — set on tool_result events to identify which tool this result came from.
  • part_index: int | None — defaults to None, which means "let the framework decide which Part this event belongs to." Pass an explicit integer only when you need to override the default grouping (see below).

How events group into Parts

When you leave part_index as None (the default), the framework groups events using these rules:

  • Consecutive same-family events concatenate. Two text events in a row become one TextPart​. Two reasoning events in a row become one ReasoningPart​. A family transition (text → reasoning, or reasoning → text) starts a new Part.
  • Tool calls group by tool_call_id​. A tool_call_name and any number of tool_call_args events sharing a tool_call_id combine into one ToolCallPart — even if they're interleaved with other events (parallel tool calls).
  • tool_result is always its own Part, paired to the originating call by tool_call_id​.
StreamResulting Parts
text × None TextPart
reasoning × N, then text × NReasoningPart, TextPart
text, tool_call_name+args, textTextPart, ToolCallPart, TextPart
Parallel tool calls (interleaved by id)one ToolCallPart per distinct tool_call_id
reasoning, tool call, reasoningReasoningPart, ToolCallPart, ReasoningPart

Setting part_index explicitly

In rare cases you'll want to override the default grouping:

  • Forcing a single TextPart across non-adjacent text bursts. If your provider interleaves text deltas with tool calls but you want all the text concatenated into one TextPart, pass part_index=0 on every text event. (The default behavior produces separate TextParts on each side of the tool calls — usually what you want, but not always.)
  • Tool-call args arriving before the id. If your provider streams args before the tool_call_id is known, assign your own index per logical tool call and pass it on each event of that call.

You can mix explicit indices with None in the same stream — the framework reserves your explicit values and decides the rest.

Reasoning tokens

For streamed reasoning text:

yield StreamEvent(type="reasoning", chunk=text_chunk)

Reasoning events that appear before/after text events become distinct ReasoningPart and TextPart entries in response.messages automatically. If your provider emits two thinking blocks separated by a tool call, you'll get two ReasoningParts.

Plugins should respect prompt.hide_reasoning​. This is set when the caller passes hide_reasoning=True to model.prompt(), conversation.prompt(), model.chain(), conversation.chain(), or their async counterparts. It is also set by the CLI -R/--hide-reasoning option.

prompt.hide_reasoning means "hide visible reasoning output", not "disable model reasoning". If your provider requires an explicit request for visible reasoning summaries, do not request those summaries when prompt.hide_reasoning is true:

kwargs = {}
if not prompt.hide_reasoning:
    kwargs["reasoning"] = {"summary": "auto"}

If your provider emits reasoning blocks regardless of request parameters, keep yielding those reasoning events as usual:

if chunk.type == "thinking":
    yield StreamEvent(type="reasoning", chunk=chunk.text)

LLM's display layers use prompt.hide_reasoning to avoid showing those events to the user, while still allowing the framework to persist ReasoningPart objects and provider metadata for logs, serialization, and future turns.

Tool calls

Each tool call emits two event types sharing a tool_call_id:

yield StreamEvent(
    type="tool_call_name",
    chunk=tool_name,
    tool_call_id=tool_call_id,
)
# then, as the provider streams JSON args:
yield StreamEvent(
    type="tool_call_args",
    chunk=partial_json_fragment,
    tool_call_id=tool_call_id,
)

The framework groups them by tool_call_id — so parallel tool calls (where args for tool A and tool B interleave on the wire) work without any per-call index tracking. Some providers (Gemini) emit the complete tool call in one chunk — it's OK to emit both events back-to-back with the full name and full JSON.

For client-side tool calls — tools that LLM should execute locally in a chain — also call response.add_tool_call()​. The chain-execution path (response.tool_calls()execute_tool_calls()) reads from the explicitly-added list, not from the StreamEvent buffer.

response.add_tool_call(
    llm.ToolCall(
        tool_call_id=tool_id,
        name=tool_name,
        arguments=parsed_args,
    )
)

Provider-managed local tool calls

Some provider SDKs orchestrate the tool loop themselves: they call a local callback with generated arguments, wait for that callback to return a result, and then continue the same model response. Plugins for those providers can delegate the actual invocation to LLM using response.execute_tool_call():

tool_result = response.execute_tool_call(
    llm.ToolCall(
        tool_call_id=tool_id,
        name=tool_name,
        arguments=parsed_args,
    )
)
return tool_result.output

Async model plugins should use the awaitable equivalent method on AsyncResponse:

tool_result = await response.execute_tool_call(
    llm.ToolCall(
        tool_call_id=tool_id,
        name=tool_name,
        arguments=parsed_args,
    )
)
return tool_result.output

This uses LLM's normal tool executor, including toolbox preparation, error handling, llm_tool_call injection and the before_call and after_call lifecycle callbacks. If tool_call_id is omitted LLM generates one.

Do not also call response.add_tool_call() for a provider-managed call. That would cause the normal chain loop to execute the same tool a second time after the provider has already received its result.

Server-side tool calls

For tools the API executes internally, set server_executed=True on the events. Anthropic web search is an example: the API returns a server_tool_use block for the search request, followed by a web_search_tool_result block containing the result payload.

yield StreamEvent(
    type="tool_call_name",
    chunk="web_search",
    tool_call_id=tool_id,
    server_executed=True,
)
yield StreamEvent(
    type="tool_call_args",
    chunk=json.dumps(query_args),
    tool_call_id=tool_id,
    server_executed=True,
)

The tool result (for example, the search hits) is also emitted as an event:

yield StreamEvent(
    type="tool_result",
    chunk=human_readable_summary,
    tool_call_id=tool_id,
    server_executed=True,
    tool_name="web_search",
    provider_metadata={"myprovider": {"raw_content": full_payload}},
)

For providers that don't stream server-tool-result contents (Anthropic's web_search_tool_result blocks only arrive in the final message), emit those results as a post-stream step. After the main iteration loop completes, inspect the final message and emit tool_result events for any server-side results.

Do not call response.add_tool_call() for server-side tool calls. This method should only be used for tool calls that need to be executed locally by the framework.

Opaque provider metadata

Some providers require you to echo back opaque fields on the next request for multi-turn continuity to work:

  • Anthropicsignature on each thinking block; encrypted_content inside web_search_tool_result items.
  • Google GeminithoughtSignature on functionCall parts when thinking is active.
  • OpenAI Responses APIencrypted_content on reasoning items in stateless mode.

These values are attached to a StreamEvent via its provider_metadata field. The framework merges metadata across events that group into the same Part (last non-None wins per top-level key) and persists it on the finalized Part.

Namespace under your provider's name so transcripts that mix providers don't collide:

# Anthropic signature arrives at the end of a thinking block.
yield StreamEvent(
    type="reasoning",
    chunk="",
    provider_metadata={"anthropic": {"signature": sig}},
)
# Gemini attaches thoughtSignature to a functionCall part.
yield StreamEvent(
    type="tool_call_name",
    chunk=name,
    tool_call_id=tc_id,
    provider_metadata={"gemini": {"thoughtSignature": sig}},
)

The framework round-trips the value verbatim via JSON, so use JSON-safe primitives (string, int, bool, dict, list) for provider metadata - use base64 encoding if you need to store binary data.

Non-streaming path

When stream=False (or the provider returns a complete message at once), emit one event per content block.

else:
    completion = client.messages.create(**kwargs)
    response.response_json = completion.model_dump()
    for block in completion.content:
        if block.type == "thinking":
            yield StreamEvent(
                type="reasoning",
                chunk=block.thinking,
                provider_metadata={"anthropic": {"signature": block.signature}},
            )
        elif block.type == "text":
            yield StreamEvent(type="text", chunk=block.text)
        elif block.type == "tool_use":
            yield StreamEvent(
                type="tool_call_name",
                chunk=block.name,
                tool_call_id=block.id,
            )
            yield StreamEvent(
                type="tool_call_args",
                chunk=json.dumps(block.input),
                tool_call_id=block.id,
            )

Condensing logged payloads with json_replacements

The raw provider payload your plugin assigns to response.response_json is logged condensed <#logging-message-store-response-json>: content that the log database already stores elsewhere - the response text, reasoning blobs, tool definitions - is replaced with references instead of being written twice.

Your model class can improve on this by declaring a json_replacements class attribute: a dictionary of payload fragments that you know recur in every response from your provider. Consult the default OpenAI plugin <https://github.com/simonw/llm/blob/main/llm/default_plugins/openai_models.py> for an example of this pattern.

class MyModel(llm.KeyModel):
    json_replacements = {
        "tool_usage_0": {
            "image_gen": {"input_tokens": 0, "output_tokens": 0},
            "web_search": {"num_requests": 0},
        },
        "response_env_0": {
            "object": "response",
            "status": "completed",
            "store": False,
        },
    }

Payload content matching an entry is stored as a reference to it. Dict entries match structurally and additionally serve as merge bases: a payload object that mostly matches an entry, such as a response envelope where only the id and usage vary per call, is stored as the base plus a patch of its differing keys.

Rules to follow:

  • Entries are append-only. Never remove or change an existing entry - only add new ones. Stored payloads reference entries by key and resolve against your dictionary when they are read back, so editing an entry silently breaks every payload already logged against it. When a provider changes a boilerplate block, append a new entry with a new suffix and leave the old one in place.
  • Reading these payloads requires your plugin to be installed: resolution looks your model up by id in the registry. If the model is unknown at read time, the payload is reported as unavailable rather than resolved incorrectly.
  • There is no size threshold for dictionary entries - you are trusted to curate them - but an entry smaller than the roughly 20-byte reference that replaces it makes payloads larger, not smaller.

Consuming prompt.messages in build_messages

prompt.messages is an list[llm.Message] that is always the complete input chain for this turn — whether the caller supplied it explicitly via model.prompt(messages=[...]), or it was synthesized from kwargs (prompt=, system=, attachments=, tool_results=), or it was pre-built by a Conversation or by response.reply()​.

Do not also walk conversation.responses​. History is already baked into prompt.messages; walking the conversation would double-emit.

A plugin's build_messages (or equivalent) iterates prompt.messages and dispatches per Part subtype:

from llm.parts import (
    TextPart,
    ReasoningPart,
    ToolCallPart,
    ToolResultPart,
    AttachmentPart,
)

def build_messages(self, prompt, conversation):
    messages = []
    for msg in prompt.messages:
        if msg.role == "system":
            # Some APIs put system on a separate kwarg (Anthropic, Gemini).
            # OpenAI-style APIs emit it as a message; handle accordingly.
            continue
        self._append_message(messages, msg)
    return messages

def _append_message(self, out, msg):
    # Map llm's role to the provider's (assistant→model for Gemini,
    # tool→user for Anthropic/Gemini tool_result convention, etc.)
    role = self._provider_role(msg.role)
    parts = []
    for part in msg.parts:
        if isinstance(part, TextPart):
            parts.append({"type": "text", "text": part.text})
        elif isinstance(part, ReasoningPart):
            # Skip redacted reasoning (no content to echo back).
            if part.redacted or not part.text:
                continue
            block = {"type": "thinking", "thinking": part.text}
            # Restore the signature from provider_metadata.
            sig = (part.provider_metadata or {}).get("anthropic", {}).get("signature")
            if sig:
                block["signature"] = sig
            parts.append(block)
        elif isinstance(part, ToolCallPart):
            parts.append({
                "type": "tool_use",
                "id": part.tool_call_id,
                "name": part.name,
                "input": part.arguments,
            })
        elif isinstance(part, ToolResultPart):
            parts.append({
                "type": "tool_result",
                "tool_use_id": part.tool_call_id,
                "content": part.output,
            })
        elif isinstance(part, AttachmentPart) and part.attachment:
            parts.append(self._attachment_block(part.attachment))
    # Merge with the previous message if roles match (some providers
    # require strict alternation between user and assistant).
    if out and out[-1]["role"] == role:
        out[-1]["content"].extend(parts)
    else:
        out.append({"role": role, "content": parts})

Restoring opaque metadata on subsequent requests

When a conversation continues, your build_messages walks prior-turn Parts via prompt.messages​. Each Part's provider_metadata is a dict[str, dict] keyed by provider name — extract your namespace and fold the fields back into the outgoing request body:

if isinstance(part, ReasoningPart):
    block = {"type": "thinking", "thinking": part.text}
    pm = (part.provider_metadata or {}).get("anthropic", {})
    if "signature" in pm:
        block["signature"] = pm["signature"]
    parts.append(block)

if isinstance(part, ToolCallPart):
    fc_part = {"function_call": {"name": part.name, "args": part.arguments}}
    pm = (part.provider_metadata or {}).get("gemini", {})
    if "thoughtSignature" in pm:
        # Gemini expects thoughtSignature beside function_call,
        # not nested inside it.
        fc_part["thoughtSignature"] = pm["thoughtSignature"]
    parts.append(fc_part)

If the key is missing (an older transcript that pre-dates your plugin's support), fall through — don't fail. Treat other providers' entries as opaque; don't parse them.

Tracking token usage

Models that charge by the token should track the number of tokens used by each prompt. The response.set_usage() method can be used to record the number of tokens used by a response - these will then be made available through the Python API and logged to the SQLite database for command-line users.

response here is the response object that is passed to ​.execute() as an argument.

Call response.set_usage() at the end of your ​.execute() method. It accepts keyword arguments input=, output= and details= - all three are optional. input and output should be integers, and details should be a dictionary that provides additional information beyond the input and output token counts.

This example logs 15 input tokens, 340 output tokens and notes that 37 tokens were cached:

response.set_usage(input=15, output=340, details={"cached": 37})

Tracking resolved model names

In some cases the model ID that the user requested may not be the exact model that is executed. Many providers have a model-latest alias which may execute different models over time.

If those APIs return the real model ID that was used, your plugin can record that in the resources.resolved_model column in the logs by calling this method and passing the string representing the resolved, final model ID:

response.set_resolved_model(resolved_model_id)

This string will be recorded in the database and shown in the output of llm logs and llm logs --json​.

Llm_raise_errors

While working on a plugin it can be useful to request that errors are raised instead of being caught and logged, so you can access them from the Python debugger.

Set the LLM_RAISE_ERRORS environment variable to enable this behavior, then run llm like this:

LLM_RAISE_ERRORS=1 python -i -m llm ...

The -i option means Python will drop into an interactive shell if an error occurs. You can then open a debugger at the most recent error using:

import pdb; pdb.pm()

Utility functions for plugins

LLM provides some utility functions that may be useful to plugins.

llm.get_key()

This method can be used to look up secrets that users have stored using the llm keys set <#help-keys-set> command. If your plugin needs to access an API key or other secret this can be a convenient way to provide that.

This returns either a string containing the key or None if the key could not be resolved.

Use the alias="name" option to retrieve the key set with that alias:

github_key = llm.get_key(alias="github")

You can also add env="ENV_VAR" to fall back to looking in that environment variable if the key has not been configured:

github_key = llm.get_key(alias="github", env="GITHUB_TOKEN")

In some cases you may allow users to provide a key as input, where they could input either the key itself or specify an alias to lookup in keys.json​. Use the input= parameter for that:

github_key = llm.get_key(input=input_from_user, alias="github", env="GITHUB_TOKEN")

An previous version of function used positional arguments in a confusing order. These are still supported but the new keyword arguments are recommended as a better way to use llm.get_key() going forward.

llm.user_dir()

LLM stores various pieces of logging and configuration data in a directory on the user's machine.

On macOS this directory is ~/Library/Application Support/io.datasette.llm, but this will differ on other operating systems.

The llm.user_dir() function returns the path to this directory as a pathlib.Path object, after creating that directory if it does not yet exist.

Plugins can use this to store their own data in a subdirectory of this directory.

import llm
user_dir = llm.user_dir()
plugin_dir = data_path = user_dir / "my-plugin"
plugin_dir.mkdir(exist_ok=True)
data_path = plugin_dir / "plugin-data.db"

llm.ModelError

If your model encounters an error that should be reported to the user you can raise this exception. For example:

import llm

raise ModelError("MPT model not installed - try running 'llm mpt30b download'")

This will be caught by the CLI layer and displayed to the user as an error message.

Response.fake()

When writing tests for a model it can be useful to generate fake response objects, for example in this test from llm-mpt30b <https://github.com/simonw/llm-mpt30b>:

def test_build_prompt_conversation():
    model = llm.get_model("mpt")
    conversation = model.conversation()
    conversation.responses = [
        llm.Response.fake(model, "prompt 1", "system 1", "response 1"),
        llm.Response.fake(model, "prompt 2", None, "response 2"),
        llm.Response.fake(model, "prompt 3", None, "response 3"),
    ]
    lines = model.build_prompt(llm.Prompt("prompt 4", model), conversation)
    assert lines == [
        "<|im_start|>system\system 1<|im_end|>\n",
        "<|im_start|>user\nprompt 1<|im_end|>\n",
        "<|im_start|>assistant\nresponse 1<|im_end|>\n",
        "<|im_start|>user\nprompt 2<|im_end|>\n",
        "<|im_start|>assistant\nresponse 2<|im_end|>\n",
        "<|im_start|>user\nprompt 3<|im_end|>\n",
        "<|im_start|>assistant\nresponse 3<|im_end|>\n",
        "<|im_start|>user\nprompt 4<|im_end|>\n",
        "<|im_start|>assistant\n",
    ]

The signature of llm.Response.fake() is:

def fake(cls, model: Model, prompt: str, system: str, response: str):

Python API

LLM provides a Python API for executing prompts, in addition to the command-line interface.

Understanding this API is also important for writing Plugins <#plugins>​.

Basic prompt execution

To run a prompt against the gpt-5.6-luna model, run this:

import llm

model = llm.get_model("gpt-5.6-luna")
# key= is optional, you can configure the key in other ways
response = model.prompt(
    "Five surprising names for a pet pelican",
    key="sk-..."
)
print(response.text())

Note that the prompt will not be evaluated until you call that response.text() method - a form of lazy loading.

If you inspect the response before it has been evaluated it will look like this:

<Response prompt='Your prompt' text='... not yet done ...'>

The llm.get_model() function accepts model IDs or aliases. You can also omit it to use the currently configured default model, which is gpt-5.6-luna if you have not changed the default.

In this example the key is set by Python code. You can also provide the key using the OPENAI_API_KEY environment variable, or use the llm keys set openai command to store it in a keys.json file, see API key management <#api-keys>​.

The __str__() method of response also returns the text of the response, so you can do this instead:

print(llm.get_model().prompt("Five surprising names for a pet pelican"))

You can run this command to see a list of available models and their aliases:

llm models

If you have set a OPENAI_API_KEY environment variable you can omit the model.key = line.

Calling llm.get_model() with an invalid model ID will raise a llm.UnknownModelError exception.

System prompts

For models that accept a system prompt, pass it as system="...":

response = model.prompt(
    "Five surprising names for a pet pelican",
    system="Answer like GlaDOS"
)

Attachments

Models that accept multi-modal input (images, audio, video etc) can be passed attachments using the attachments= keyword argument. This accepts a list of llm.Attachment() instances.

This example shows two attachments - one from a file path and one from a URL:

import llm

model = llm.get_model("gpt-5.6-luna")
response = model.prompt(
    "Describe these images",
    attachments=[
        llm.Attachment(path="pelican.jpg"),
        llm.Attachment(url="https://static.simonwillison.net/static/2024/pelicans.jpg"),
    ]
)

Use llm.Attachment(content=b"binary image content here") to pass binary content directly.

class llm.Attachment(type: str | None = None, path: str | None = None, url: str | None = None, content: bytes | None = None, _id: str | None = None)

An attachment (image, audio, etc) to include with a prompt.

base64_content()

Return the content as a base64-encoded string.

content_bytes()

Return the binary content, reading from path or URL if needed.

resolve_type()

Return the content type, guessing from content if not specified.

You can check which attachment types (if any) a model supports using the model.attachment_types set:

model = llm.get_model("gpt-5.6-luna")
print(model.attachment_types)
# {'image/gif', 'image/png', 'image/jpeg', 'image/webp'}

if "image/jpeg" in model.attachment_types:
    # Use a JPEG attachment here
    ...

Tools

Tools <#tools> are functions that can be executed by the model as part of a chain of responses.

You can define tools in Python code - with a docstring to describe what they do - and then pass them to the model.prompt() method using the tools= keyword argument. If the model decides to request a tool call the response.tool_calls() method show what the model wants to execute:

import llm

def upper(text: str) -> str:
    """Convert text to uppercase."""
    return text.upper()

model = llm.get_model("gpt-4.1-mini")
response = model.prompt("Convert panda to upper", tools=[upper])
tool_calls = response.tool_calls()
# [ToolCall(name='upper', arguments={'text': 'panda'}, tool_call_id='...')]

Every tool call is guaranteed to have a unique tool_call_id​. Most providers supply their own; for providers that do not, LLM synthesizes one of the form tc_01..., so you can always use the id to correlate a tool call with its result or to key external state against a specific invocation. You can call response.execute_tool_calls() to execute those calls and get back the results:

tool_results = response.execute_tool_calls()
# [ToolResult(name='upper', output='PANDA', tool_call_id='...')]

To get the model's follow-up reply, call response.reply() — when the previous response made tool calls, reply() automatically executes them and feeds the results back into the next turn:

follow_up = response.reply()
print(follow_up.text())
# The word "panda" converted to uppercase is "PANDA".

You can also pass an additional user prompt: response.reply("now translate it to French")​. To use custom or already-computed tool results (e.g. results you mutated, or synthetic ones for testing) pass them explicitly with tool_results= and the auto-execute step is skipped:

follow_up = response.reply(
    "now translate it",
    tool_results=[llm.ToolResult(name="upper", output="PANDA", tool_call_id="...")],
)

For an automatic loop that keeps going until the model stops requesting tools, use model.chain() — it passes tool call results back to the model automatically as subsequent prompts:

chain_response = model.chain(
    "Convert panda to upper",
    tools=[upper],
)
print(chain_response.text())
# The word "panda" converted to uppercase is "PANDA".

You can also loop through the model.chain() response to get a stream of tokens, like this:

for chunk in model.chain(
    "Convert panda to upper",
    tools=[upper],
):
    print(chunk, end="", flush=True)

This will stream each of the chain of responses in turn as they are generated.

You can access the individual responses that make up the chain using chain.responses()​. This can be iterated over as the chain executes like this:

chain = model.chain(
    "Convert panda to upper",
    tools=[upper],
)
for response in chain.responses():
    print(response.prompt)
    for chunk in response:
        print(chunk, end="", flush=True)

Tool debugging hooks

Pass a function to the before_call= parameter of model.chain() to have that called before every tool call is executed. You can raise llm.CancelToolCall() to cancel that tool call.

The method signature is def before_call(tool: llm.Tool | None, tool_call: llm.ToolCall) - that first tool argument can be None if the model requests a tool be executed that has not been provided in the tools= list.

Here's an example:

import llm

def upper(text: str) -> str:
    "Convert text to uppercase."
    return text.upper()

def before_call(tool: llm.Tool | None, tool_call: llm.ToolCall):
    tool_name = tool.name if tool is not None else tool_call.name
    print(f"About to call tool {tool_name} with arguments {tool_call.arguments}")
    if tool_name == "upper" and "bad" in repr(tool_call.arguments):
        raise llm.CancelToolCall("Not allowed to call upper on text containing 'bad'")

model = llm.get_model("gpt-4.1-mini")
response = model.chain(
    "Convert panda to upper and badger to upper",
    tools=[upper],
    before_call=before_call,
)
print(response.text())

If you raise llm.CancelToolCall in the before_call function the model will be informed that the tool call was cancelled.

The after_call= parameter can be used to run a logging function after each tool call has been executed. The method signature is def after_call(tool: llm.Tool, tool_call: llm.ToolCall, tool_result: llm.ToolResult)​. This continues the previous example:

def after_call(tool: llm.Tool, tool_call: llm.ToolCall, tool_result: llm.ToolResult):
    print(f"Tool {tool.name} called with arguments {tool_call.arguments} returned {tool_result.output}")

response = model.chain(
    "Convert panda to upper and badger to upper",
    tools=[upper],
    after_call=after_call,
)
print(response.text())

Accessing the tool call from inside a tool

Tool implementations sometimes need to know about the llm.ToolCall that triggered them - most often the tool_call_id (always populated, see above), which can be used to key external state against that specific invocation.

If your tool function accepts a parameter named llm_tool_call it will be passed the llm.ToolCall object for the current call:

import llm

def lookup(name: str, llm_tool_call: llm.ToolCall) -> str:
    "Look up a name."
    return do_lookup(name, request_id=llm_tool_call.tool_call_id)

The llm_tool_call parameter name is reserved: it is excluded from the input schema that is exposed to the model and is populated automatically when the tool executes. The type annotation is optional.

This works for both sync and async tool functions, and for methods on llm.Toolbox subclasses. The parameter must be declared explicitly - a **kwargs catch-all will not receive llm_tool_call​.

Pausing a chain from inside a tool

Sometimes a tool cannot finish without outside input - human approval being the classic case. Raise llm.PauseChain inside a tool implementation to stop the chain cleanly:

import llm

def delete_files(path: str) -> str:
    if not approval_already_recorded(path):
        record_approval_request(path)
        raise llm.PauseChain("waiting for approval to delete " + path)
    do_delete(path)
    return "deleted"

Unlike other exceptions - which are converted into "Error: ..." tool results and sent back to the model - PauseChain propagates out of the chain to your code. No provider call is made with a placeholder result. Before re-raising, the framework populates two attributes:

  • pause.tool_call - the llm.ToolCall whose implementation paused
  • pause.tool_results - results of sibling calls in the same batch that completed

    try:
        chain_response.text()
    except llm.PauseChain as pause:
        print("Paused on", pause.tool_call.name, pause.tool_call.tool_call_id)

The failure semantics are defined: concurrent (async) sibling tool calls always run to completion before the exception propagates - their after_call hooks fire and their results are preserved - while sequential (sync) execution stops at the paused call, leaving later calls unexecuted so they can safely run on resume. If several concurrent calls pause, the first by call order propagates. after_call does not fire for a paused call, and no ToolResult is recorded for it - which is what marks it as still pending.

Resuming a chain with pending tool calls

To resume after a pause (or a crash, or a server restart), re-run the chain with a messages= history that ends in the unresolved tool calls. When the last assistant message in the history contains tool calls that have no matching results, the chain executes them first - through the normal before_call/after_call machinery - and then sends the results to the model:

chain = model.chain(
    messages=persisted_messages,  # ends in assistant tool calls with no results
    tools=[delete_files],
    system=system_prompt,
)
chain.text()

Calls that already have results in trailing tool-role messages are skipped, so a batch where some calls completed before the pause only re-executes the unresolved ones. A re-executed tool may raise PauseChain again - multi-step approval flows work by repeating the cycle. If a user or assistant message follows the tool calls in the history, the conversation has moved on and nothing is re-executed.

Matching uses tool_call_id (always populated for newly-created tool calls); id-less calls from older persisted histories match results by name. You can also execute an explicit list of calls directly with response.execute_tool_calls(tool_calls_list=[...])​.

Tools can return attachments

Tools can return attachments in addition to returning text. Attachments that are returned from a tool call will be passed to the model as attachments for the next prompt in the chain.

To return one or more attachments, return a llm.ToolOutput instance from your tool function. This can have an output= string and an attachments= list of llm.Attachment instances.

Here's an example:

import llm

def generate_image(prompt: str) -> llm.ToolOutput:
    """Generate an image based on the prompt."""
    image_content = generate_image_from_prompt(prompt)
    return llm.ToolOutput(
        output="Image generated successfully",
        attachments=[llm.Attachment(
            content=image_content,
            mimetype="image/png"
        )],
    )
class llm.ToolOutput(output: str | dict | list | bool | int | float | None = None, attachments: list[Attachment <#llm.Attachment>] = <factory>)

Tool functions can return output with extra attachments

Server-side tools

Server-side tools are executed by the model provider during a response. Pass them in the same tools= list as function tools, but do not call execute_tool_calls() for them: their calls and results arrive in response.messages() with server_executed=True and are excluded from the local execution loop.

For example, OpenAI Responses models support Web Search <#openai-models-web-search> and Code Interpreter <#openai-models-code-interpreter>:

import llm
from llm.default_plugins.openai_models import CodeInterpreter

response = llm.get_model("gpt-5.6-luna").prompt(
    "Use the python tool to calculate the first 20 Fibonacci numbers",
    tools=[CodeInterpreter(memory_limit="4g")],
)
print(response.text())

Provider plugins define these tools by subclassing llm.ServerSideTool <#llm.ServerSideTool>​. Each model instance returns its supported classes from supported_server_side_tools; a model rejects classes it has not explicitly included rather than silently dropping them. See Supporting server-side tools <#advanced-model-plugins-server-side-tools> for the plugin API.

Toolbox classes

Functions are useful for simple tools, but some tools may have more advanced needs. You can also define tools as a class (known as a "toolbox"), which provides the following advantages:

  • Toolbox tools can bundle multiple tools together
  • Toolbox tools can be configured, e.g. to give filesystem tools access to a specific directory
  • Toolbox instances can persist shared state in between tool invocations

Toolboxes are classes that extend llm.Toolbox​. Any methods that do not begin with an underscore will be exposed as tool functions.

This example sets up key/value memory storage that can be used by the model:

import llm

class Memory(llm.Toolbox):
    _memory = None

    def _get_memory(self):
        if self._memory is None:
            self._memory = {}
        return self._memory

    def set(self, key: str, value: str):
        "Set something as a key"
        self._get_memory()[key] = value

    def get(self, key: str):
        "Get something from a key"
        return self._get_memory().get(key) or ""

    def append(self, key: str, value: str):
        "Append something as a key"
        memory = self._get_memory()
        memory[key] = (memory.get(key) or "") + "\n" + value

    def keys(self):
        "Return a list of keys"
        return list(self._get_memory().keys())
class llm.Toolbox
add_tool(tool_or_function: Tool <#llm.Tool> | Callable[[​...], Any], pass_self: bool = False)

Add a tool to this toolbox

prepare()

Over-ride this to perform setup (and .add_tool() calls) before the toolbox is used. Implement a similar prepare_async() method for async setup.

async prepare_async()

Over-ride this to perform async setup (and .add_tool() calls) before the toolbox is used.

tools() -> Iterable[Tool <#llm.Tool>]

Returns an llm.Tool() for each class method, plus any extras registered with add_tool()

You can then use that from Python like this:

model = llm.get_model("gpt-4.1-mini")
memory = Memory()

conversation = model.conversation(tools=[memory])
print(conversation.chain("Set name to Simon", after_call=print).text())

print(memory._memory)
# Should show {'name': 'Simon'}

print(conversation.chain("Set name to Penguin", after_call=print).text())
# Now it should be {'name': 'Penguin'}

print(conversation.chain("Print current name", after_call=print).text())

See the register_tools() plugin hook documentation <#plugin-hooks-register-tools> for an example of this tool in action as a CLI plugin.

Dynamic toolboxes

Sometimes you may need to register additional tools against a toolbox after it has been created - for example if you are implementing an MCP plugin where the toolbox needs to consult the MCP server to discover what tools are available.

You can use the toolbox.add_tool(function_or_tool) method to add a new tool to an existing toolbox.

This can be passed a llm.Tool instance or a function that will be converted into a tool automatically.

If you want your function to be able to access the toolbox instance itself as a self parameter, pass that function to add_tool() with the pass_self=True parameter:

def my_function(self, arg1: str, arg2: int) -> str:
    return f"Received {arg1} and {arg2} in {self}"

toolbox.add_tool(my_function, pass_self=True)

Without pass_self=True the function will be called with only its declared arguments, with no self parameter.

If your toolbox needs to run an additional command to figure out what it should register using ​.add_tool() you can implement a prepare() method on your toolbox class. This will be called once automatically when the toolbox is first used.

In asynchronous contexts the alternative method await toolbox.prepare_async() method will be called before the toolbox is used. You can implement this method on your subclass and use it to run asynchronous operations that discover tools to be registered using self.add_tool()​.

If you want to prepare the class in this way such that it can be used in both synchronous and asynchronous contexts, implement both prepare() and prepare_async() methods.

Toolbox classes that override tools(), prepare() or prepare_async() are treated as dynamic by the llm tools command. Since their full list of tools cannot be determined until an instance has been configured, llm tools displays their constructor signature and class docstring instead of a list of tools - so give your dynamic toolbox a descriptive docstring that shows how to configure it. Users can then pass a full specification such as llm tools 'MCP("https://example.com/mcp")' to instantiate the toolbox - running prepare() if it is implemented - and list the tools that instance provides. See the tools usage documentation <#usage-tools> for details.

Schemas

As with the CLI tool <#usage-schemas> some models support passing a JSON schema should be used for the resulting response.

You can pass this to the prompt(schema=) parameter as either a Python dictionary or a Pydantic <https://docs.pydantic.dev/> BaseModel subclass:

import llm, json
from pydantic import BaseModel

class Dog(BaseModel):
    name: str
    age: int

model = llm.get_model("gpt-5.6-luna")
response = model.prompt("Describe a nice dog", schema=Dog)
dog = json.loads(response.text())
print(dog)
# {"name":"Buddy","age":3}

You can also pass a schema directly, like this:

response = model.prompt("Describe a nice dog", schema={
    "properties": {
        "name": {"title": "Name", "type": "string"},
        "age": {"title": "Age", "type": "integer"},
    },
    "required": ["name", "age"],
    "title": "Dog",
    "type": "object",
})

You can also use LLM's alternative schema syntax <#schemas-dsl> via the llm.schema_dsl(schema_dsl) function. This provides a quick way to construct a JSON schema for simple cases:

print(model.prompt(
    "Describe a nice dog with a surprising name",
    schema=llm.schema_dsl("name, age int, bio")
))

Pass multi=True to generate a schema that returns multiple items matching that specification:

print(model.prompt(
    "Describe 3 nice dogs with surprising names",
    schema=llm.schema_dsl("name, age int, bio", multi=True)
))

Fragments

The fragment system <#usage-fragments> from the CLI tool can also be accessed from the Python API, by passing fragments= and/or system_fragments= lists of strings to the prompt() method:

from pathlib import Path

response = model.prompt(
    "What do these documents say about dogs?",
    fragments=[
        Path("dogs1.txt").read_text(),
        Path("dogs2.txt").read_text(),
    ],
    system_fragments=[
        "You answer questions like Snoopy",
    ]
)

This mechanism has limited utility in Python, as you can also assemble the contents of these strings together into the prompt= and system= strings directly.

Fragments become more interesting if you are working with LLM's mechanisms for storing prompts to a SQLite database, which are not yet part of the stable, documented Python API.

Some model plugins may include features that take advantage of fragments, for example llm-anthropic <https://github.com/simonw/llm-anthropic> aims to use them as part of a mechanism that taps into Claude's prompt caching system.

Model options

For models that support options (view those with llm models --options) pass them as a dictionary to the options= argument of the ​.prompt() method:

model = llm.get_model()
print(model.prompt("Names for otters", options={"temperature": 0.2}))

Passing an API key

Models that accept API keys should take an additional key= parameter to their model.prompt() method:

model = llm.get_model("gpt-5.6-luna")
print(model.prompt("Names for beavers", key="sk-..."))

If you don't provide this argument LLM will attempt to find it from an environment variable (OPENAI_API_KEY for OpenAI, others for different plugins) or from keys that have been saved using the llm keys set <#api-keys> command.

Some model plugins may not yet have been upgraded to handle the key= parameter, in which case you will need to use one of the other mechanisms.

Models from plugins

Any models you have installed as plugins will also be available through this mechanism, for example to use Anthropic's Claude 3.5 Sonnet model with llm-anthropic <https://github.com/simonw/llm-anthropic>:

pip install llm-anthropic

Then in your Python code:

import llm

model = llm.get_model("claude-sonnet-5")
# Use this if you have not set the key using 'llm keys set anthropic':
model.key = 'YOUR_API_KEY_HERE'
response = model.prompt("Five surprising names for a pet pelican")
print(response.text())

Some models do not use API keys at all.

Accessing the underlying JSON

Most model plugins also make a JSON version of the prompt response available. The structure of this will differ between model plugins, so building against this is likely to result in code that only works with that specific model provider.

You can access this JSON data as a Python dictionary using the response.json() method:

import llm
from pprint import pprint

model = llm.get_model("gpt-5.6-luna")
response = model.prompt("3 names for an otter")
json_data = response.json()
pprint(json_data)

Here's an abbreviated example of that output from GPT-5.6 Luna:

{'created_at': 1785451200.0,
 'id': 'resp_...',
 'model': 'gpt-5.6-luna',
 'object': 'response',
 'output': [
     # Reasoning and message items are abbreviated here
     {'content': [{'annotations': [],
                   'text': '1. Splash\n2. Bubbles\n3. Otto',
                   'type': 'output_text'}],
      'id': 'msg_...',
      'role': 'assistant',
      'status': 'completed',
      'type': 'message'}],
 'status': 'completed',
 'usage': {'input_tokens': 13,
           'output_tokens': 43,
           'output_tokens_details': {'reasoning_tokens': 0},
           'total_tokens': 56}}

Token usage

Many models can return a count of the number of tokens used while executing the prompt.

The response.usage() method provides an abstraction over this:

pprint(response.usage())

Example output:

Usage(input=5,
      output=2,
      details={'candidatesTokensDetails': [{'modality': 'TEXT',
                                            'tokenCount': 2}],
               'promptTokensDetails': [{'modality': 'TEXT', 'tokenCount': 5}]})
class llm.Usage(input: int | None = None, output: int | None = None, details: dict[str, Any] | None = None)

Token usage information from a model response.

Streaming responses

For models that support it you can stream responses as they are generated, like this:

response = model.prompt("Five diabolical names for a pet goat")
for chunk in response:
    print(chunk, end="")

The response.text() method described earlier does this for you - it runs through the iterator and gathers the results into a string.

If a response has been evaluated, response.text() will continue to return the same string.

class llm.Response(prompt: Prompt <#llm.Prompt>, model: _BaseModel, stream: bool, conversation: _BaseConversation | None = None, key: str | None = None, before_call: Callable[[Tool <#llm.Tool> | None, ToolCall <#llm.ToolCall>], None] | Callable[[Tool <#llm.Tool> | None, ToolCall <#llm.ToolCall>], None | Awaitable[None]] | None = None, after_call: Callable[[Tool <#llm.Tool>, ToolCall <#llm.ToolCall>, ToolResult <#llm.ToolResult>], None] | Callable[[Tool <#llm.Tool>, ToolCall <#llm.ToolCall>, ToolResult <#llm.ToolResult>], None | Awaitable[None]] | None = None)

Sync response from a model.

json() -> dict[str, Any] | None

Return the raw JSON response from the model, if available.

on_done(callback)

Register a callback to be called when the response is complete.

text() -> str

Return the full text of the response, executing the prompt if needed.

tool_calls() -> list[ToolCall <#llm.ToolCall>]

Return the list of tool calls made during this response.

usage() -> Usage <#llm.Usage>

Return token usage information for this response.

Structured messages and streaming events

Many LLMs return structure that goes beyond a plain text response. LLM represents these using messages that consist of parts​.

A conversation consists of turns, where each turn is an llm.Message with a role ("user", "assistant", "system", or "tool") and a list of Part objects — TextPart, ReasoningPart, ToolCallPart, ToolResultPart, or AttachmentPart​.

You can pass structured prompt inputs via messages=[...], iterate over typed events as the model streams, and inspect the assembled message after the response completes.

Here's how to prompt a model with a list of messages instead of a plain text prompt:

import llm
from llm import user, assistant, system

model = llm.get_model("gpt-5.4-mini")

response = model.prompt(messages=[
    system("You are a helpful pirate."),
    user("What is the capital of France?"),
    assistant("Paris, matey."),
    user("And Germany?"),
])
print(response.text())

The user(), assistant(), and system() helpers accept strings (wrapped as TextPart) but can also accept llm.Attachment instances (wrapped as AttachmentPart) or more complex sequences of Part objects.

Calling model.prompt("hi", system="Be brief.") is equivalent to model.prompt(messages=[system("Be brief."), user("hi")])​.

Streaming events as they arrive

response.stream_events() yields typed events for every content block the model produces as they stream in. This is useful for interfaces that show the model response "live".

response = model.prompt("Explain quantum computing briefly.")
for event in response.stream_events():
    if event.type == "reasoning":
        print(f"[thinking] {event.chunk}", end="", flush=True)
    elif event.type == "text":
        print(event.chunk, end="", flush=True)
    elif event.type == "tool_call_name":
        print(f"\n[calling tool: {event.chunk}]")
    elif event.type == "tool_call_args":
        print(event.chunk, end="", flush=True)

Event types are "text", "reasoning", "tool_call_name", "tool_call_args", and "tool_result"​. Each event carries a part_index that groups events into the same logical Part (all events at the same part_index assemble into one Part after the stream completes). For async models, use async for event in response.astream_events()​.

Iterating against the response object itself (for chunk in response) yields only text strings — reasoning and tool-call events are filtered out.

Hiding reasoning output

Some model plugins can return visible reasoning text, exposed as "reasoning" events from response.stream_events() and assembled as ReasoningPart objects in response.messages()​.

Pass hide_reasoning=True to ask LLM and supported model plugins not to expose that visible reasoning output:

response = model.prompt(
    "Explain quantum computing briefly.",
    hide_reasoning=True,
)
print(response.text())

This is the Python API equivalent of the CLI -R/--hide-reasoning option. It is available on model.prompt(), conversation.prompt(), model.chain(), conversation.chain(), and their async counterparts.

Note that this only requests that the underlying model does not return visible tokens. This request may not be supported by your provider, in which case this hint will not prevent visible reasoning tokens from being returned in the stream.

Inspecting the finished response

response.messages() returns the assembled list of Message objects produced by the model, excluding the messages from the original prompt. Calling it forces execution if the response hasn't been drained yet, so you don't need a separate response.text() first:

response = model.prompt("What's 2+2?")
for message in response.messages():
    for part in message.parts:
        print(type(part).__name__, part.to_dict())

On async models messages() is awaitable: await response.messages()​.

Persisting a conversation

A Response can round-trip through a plain Python dictionary via response.to_dict() and llm.Response.from_dict(...)​. The dict captures the model id, the input messages that were sent, the assistant output, and any options. The re-inflated object can be used to continue the conversation.

Use response.reply(...) to continue from a rehydrated response:

import json
import llm

model = llm.get_model("gpt-5.4-mini")
response = model.prompt("What's 2+2?")
print(response.text())

payload = json.dumps(response.to_dict())
# ...save `payload` wherever you want...

# Later — rehydrate and continue.
rebuilt = llm.Response.from_dict(json.loads(payload))
followup = rebuilt.reply("Add 3 to that")
print(followup.text())

AttachmentPart bytes are base64-encoded in the dict form, so multi-modal conversations round-trip via JSON too.

Individual Message and Part objects also support to_dict() / from_dict() if you need to manipulate turns directly — for example, to edit, filter, or splice messages before passing them back via model.prompt(messages=[...])​.

Async models

Some plugins provide async versions of their supported models, suitable for use with Python asyncio <https://docs.python.org/3/library/asyncio.html>​.

To use an async model, use the llm.get_async_model() function instead of llm.get_model():

import llm
model = llm.get_async_model("gpt-4o")

You can then run a prompt using await model.prompt(...):

print(await model.prompt(
    "Five surprising names for a pet pelican"
).text())

Or use async for chunk in ... to stream the response as it is generated:

async for chunk in model.prompt(
    "Five surprising names for a pet pelican"
):
    print(chunk, end="", flush=True)
class llm.AsyncResponse(prompt: Prompt <#llm.Prompt>, model: _BaseModel, stream: bool, conversation: _BaseConversation | None = None, key: str | None = None, before_call: Callable[[Tool <#llm.Tool> | None, ToolCall <#llm.ToolCall>], None] | Callable[[Tool <#llm.Tool> | None, ToolCall <#llm.ToolCall>], None | Awaitable[None]] | None = None, after_call: Callable[[Tool <#llm.Tool>, ToolCall <#llm.ToolCall>, ToolResult <#llm.ToolResult>], None] | Callable[[Tool <#llm.Tool>, ToolCall <#llm.ToolCall>, ToolResult <#llm.ToolResult>], None | Awaitable[None]] | None = None)

Async response from a model.

async json() -> dict[str, Any] | None

Return the raw JSON response from the model, if available.

async on_done(callback)

Register a callback to be called when the response is complete.

async text() -> str

Return the full text of the response, executing the prompt if needed.

async tool_calls() -> list[ToolCall <#llm.ToolCall>]

Return the list of tool calls made during this response.

async usage() -> Usage <#llm.Usage>

Return token usage information for this response.

This await model.prompt() method takes the same arguments as the synchronous model.prompt() method, for options and attachments and key= and suchlike.

Tool functions can be sync or async

Tool functions can be both synchronous or asynchronous. The latter are defined using async def tool_name(...)​. Either kind of function can be passed to the tools=[...] parameter.

If an async def function is used in a synchronous context LLM will automatically execute it in a thread pool using asyncio.run()​. This means the following will work even in non-asynchronous Python scripts:

async def hello(name: str) -> str:
    "Say hello to name"
    return "Hello there " + name

model = llm.get_model("gpt-4.1-mini")
chain_response = model.chain(
    "Say hello to Percival", tools=[hello]
)
print(chain_response.text())

This also works for async def methods of llm.Toolbox subclasses.

Tool use for async models

Tool use is also supported for async models, using either synchronous or asynchronous tool functions. Synchronous functions will block the event loop so only use those in asynchronous context if you are certain they are extremely fast.

The response.execute_tool_calls() and chain_response.text() and chain_response.responses() methods must all be awaited when run against asynchronous models:

import llm
model = llm.get_async_model("gpt-4.1")

def upper(string):
    "Converts string to uppercase"
    return string.upper()

chain = model.chain(
    "Convert panda to uppercase then pelican to uppercase",
    tools=[upper],
    after_call=print
)
print(await chain.text())

To iterate over the chained response output as it arrives use async for:

async for chunk in model.chain(
    "Convert panda to uppercase then pelican to uppercase",
    tools=[upper]
):
    print(chunk, end="", flush=True)

response.reply() is awaitable on async models — it awaits execute_tool_calls() internally before building the next turn:

response = model.prompt("Convert panda to upper", tools=[upper])
await response.text()
follow_up = await response.reply()
print(await follow_up.text())

The before_call and after_call hooks can be async functions when used with async models.

Conversations

LLM supports conversations, where you ask follow-up questions of a model as part of an ongoing conversation.

To start a new conversation, use the model.conversation() method:

model = llm.get_model()
conversation = model.conversation()

You can then use the conversation.prompt() method to execute prompts against this conversation:

response = conversation.prompt("Five fun facts about pelicans")
print(response.text())

This works exactly the same as the model.prompt() method, except that the conversation will be maintained across multiple prompts. So if you run this next:

response2 = conversation.prompt("Now do skunks")
print(response2.text())

You will get back five fun facts about skunks.

The conversation.prompt() method supports attachments as well:

response = conversation.prompt(
    "Describe these birds",
    attachments=[
        llm.Attachment(url="https://static.simonwillison.net/static/2024/pelicans.jpg")
    ]
)

Access conversation.responses for a list of all of the responses that have so far been returned during the conversation.

Conversations using tools

You can pass a list of tool functions to the tools=[] argument when you start a new conversation:

import llm

def upper(text: str) -> str:
    "convert text to upper case"
    return text.upper()

def reverse(text: str) -> str:
    "reverse text"
    return text[::-1]

model = llm.get_model("gpt-4.1-mini")
conversation = model.conversation(tools=[upper, reverse])

You can then call the conversation.chain() method multiple times to have a conversation that uses those tools:

print(conversation.chain(
    "Convert panda to uppercase and reverse it"
).text())
print(conversation.chain(
    "Same with pangolin"
).text())

The before_call= and after_call= parameters described above can be passed directly to the model.conversation() method to set those options for all chained prompts in that conversation.

Listing models

The llm.get_models() list returns a list of all available models, including those from plugins.

import llm

for model in llm.get_models():
    print(model.model_id)

Use llm.get_async_models() to list async models:

for model in llm.get_async_models():
    print(model.model_id)

Running code when a response has completed

For some applications, such as tracking the tokens used by an application, it may be useful to execute code as soon as a response has finished being executed

You can do this using the response.on_done(callback) method, which causes your callback function to be called as soon as the response has finished (all tokens have been returned).

The signature of the method you provide is def callback(response) - it can be optionally an async def method when working with asynchronous models.

Example usage:

import llm

model = llm.get_model("gpt-5.6-luna")
response = model.prompt("a poem about a hippo")
response.on_done(lambda response: print(response.usage()))
print(response.text())

Which outputs:

Usage(input=20, output=494, details={})
In a sunlit glade by a bubbling brook,
Lived a hefty hippo, with a curious look.
​...

Or using an asyncio model, where you need to await response.on_done(done) to queue up the callback:

import asyncio, llm

async def run():
    model = llm.get_async_model("gpt-5.6-luna")
    response = model.prompt("a short poem about a brick")
    async def done(response):
        print(await response.usage())
        print(await response.text())
    await response.on_done(done)
    print(await response.text())

asyncio.run(run())

Other functions

The llm top level package includes some useful utility functions.

set_alias(alias, model_id)

The llm.set_alias() function can be used to define a new alias:

import llm

llm.set_alias("mini", "gpt-5.6-luna")

The second argument can be a model identifier or another alias, in which case that alias will be resolved.

If the aliases.json file does not exist or contains invalid JSON it will be created or overwritten.

remove_alias(alias)

Removes the alias with the given name from the aliases.json file.

Raises KeyError if the alias does not exist.

import llm

llm.remove_alias("turbo")

set_default_model(alias)

This sets the default model to the given model ID or alias. Any changes to defaults will be persisted in the LLM configuration folder, and will affect all programs using LLM on the system, including the llm CLI tool.

import llm

llm.set_default_model("claude-5-sonnet")

get_default_model()

This returns the currently configured default model, or gpt-5.6-luna if no default has been set.

import llm

model_id = llm.get_default_model()

To detect if no default has been set you can use this pattern:

if llm.get_default_model(default=None) is None:
    print("No default has been set")

Here the default= parameter specifies the value that should be returned if there is no configured default.

set_default_embedding_model(alias) and get_default_embedding_model()

These two methods work the same as set_default_model() and get_default_model() but for the default embedding model <#embeddings> instead.

Logging to SQLite

llm defaults to logging all prompts and responses to a SQLite database.

You can find the location of that database using the llm logs path command:

llm logs path

On my Mac that outputs:

/Users/simon/Library/Application Support/io.datasette.llm/logs.db

This will differ for other operating systems.

To avoid logging an individual prompt, pass --no-log or -n to the command:

llm 'Ten names for cheesecakes' -n

To turn logging by default off:

llm logs off

If you've turned off logging you can still log an individual prompt and response by adding --log:

llm 'Five ambitious names for a pet pterodactyl' --log

To turn logging by default back on again:

llm logs on

To see the status of the logs database, run this:

llm logs status

Example output:

Logging is ON for all prompts
Found log database at /Users/simon/Library/Application Support/io.datasette.llm/logs.db
Number of threads logged:       33
Number of turns logged:         48
Database file size:             19.96MB

Viewing the logs

You can view the logs using the llm logs command:

llm logs

This will output the three most recent logged items in Markdown format, showing both the prompt and the response formatted using Markdown.

To get back just the most recent prompt response as plain text, add -r/--response:

llm logs -r

Use -x/--extract to extract and return the first fenced code block from the selected log entries:

llm logs --extract

Or --xl/--extract-last for the last fenced code block:

llm logs --extract-last

Add --json to get the log messages in JSON instead:

llm logs --json

Add -n 10 to see the ten most recent items:

llm logs -n 10

Or -n 0 to see everything that has ever been logged:

llm logs -n 0

You can truncate the display of the prompts and responses using the -t/--truncate option. This can help make the JSON output more readable - though the --short option is usually better.

llm logs -n 1 -t --json

Example output:

[
  {
    "id": "01jm8ec74wxsdatyn5pq1fp0s5",
    "model": "anthropic/claude-3-haiku-20240307",
    "prompt": "hi",
    "system": null,
    "prompt_json": null,
    "response": "Hello! How can I assist you today?",
    "conversation_id": "01jm8ec74taftdgj2t4zra9z0j",
    "duration_ms": 560,
    "datetime_utc": "2025-02-16T22:34:30.374882+00:00",
    "input_tokens": 8,
    "output_tokens": 12,
    "token_details": null,
    "conversation_name": "hi",
    "conversation_model": "anthropic/claude-3-haiku-20240307",
    "attachments": []
  }
]

-s/--short mode

Use -s/--short to see a shortened YAML log with truncated prompts and no responses:

llm logs -n 2 --short

Example output:

- model: deepseek-reasoner
  datetime: '2025-02-02T06:39:53'
  conversation: 01jk2pk05xq3d0vgk0202zrsg1
  prompt:  H01 There are five huts. H02 The Scotsman lives in the purple hut. H03 The Welshman owns the parrot. H04 Kombucha is...
- model: o3-mini
  datetime: '2025-02-02T19:03:05'
  conversation: 01jk40qkxetedzpf1zd8k9bgww
  system: Formatting re-enabled. Write a detailed README with extensive usage examples.
  prompt: <documents> <document index="1"> <source>./Cargo.toml</source> <document_content> [package] name = "py-limbo" version...

Include -u/--usage to include token usage information:

llm logs -n 1 --short --usage

Example output:

- model: o3-mini
  datetime: '2025-02-16T23:00:56'
  conversation: 01jm8fxxnef92n1663c6ays8xt
  system: Produce Python code that demonstrates every possible usage of yaml.dump
    with all of the arguments it can take, especi...
  prompt: <documents> <document index="1"> <source>./setup.py</source> <document_content>
    NAME = 'PyYAML' VERSION = '7.0.0.dev0...
  usage:
    input: 74793
    output: 3550
    details:
      completion_tokens_details:
        reasoning_tokens: 2240

Logs for a conversation

To view the logs for the most recent conversation <#usage-conversation> you have had with a model, use -c:

llm logs -c

To see logs for a specific conversation based on its ID, use --cid ID or --conversation ID:

llm logs --cid 01h82n0q9crqtnzmf13gkyxawg

Searching the logs

You can search the logs for a search term across your prompts and the model's responses.

llm logs -q 'cheesecake'

The most relevant results will be shown first.

Search covers the text you typed and the text the model produced, and nothing else. System prompts, fragment <#fragments> contents, tool calls and their output, and reasoning traces are all excluded from the index - a query only matches words that appeared in a prompt or a response. If a prompt used fragments, the fragment text is not searchable but the question you typed alongside it is.

Ranking uses SQLite FTS5 <https://www.sqlite.org/fts5.html> relevance scores, with matches in your prompt weighted well above matches in the response - what you asked is usually a stronger signal of what a conversation was about than what came back. The full FTS5 query syntax <https://www.sqlite.org/fts5.html#full_text_query_syntax> is available, including phrase queries:

llm logs -q '"pet pelican"'

To switch to sorting with most recent first, add -l/--latest​. This can be combined with -n to limit the number of results shown:

llm logs -q 'cheesecake' -l -n 3

Search covers both new conversations and history recorded by older versions of LLM.

Filtering past a specific ID

If you want to retrieve all of the logs that were recorded since a specific response ID you can do so using these options:

  • --id-gt $ID - every record with an ID greater than $ID
  • --id-gte $ID - every record with an ID greater than or equal to $ID

IDs are always issued in ascending order by time, so this provides a useful way to see everything that has happened since a particular record.

This can be particularly useful when working with schema data <#schemas-logs>, where you might want to access every record that you have created using a specific --schema but exclude records you have previously processed.

Filtering by model

You can filter to logs just for a specific model (or model alias) using -m/--model:

llm logs -m chatgpt

Filtering by prompts that used specific fragments

The -f/--fragment X option will filter for just responses that were created using the specified fragment <#usage-fragments> hash or alias or URL or filename.

Fragments are displayed in the logs as their hash ID. Add -e/--expand to display fragments as their full content - this option works for both the default Markdown and the --json mode:

llm logs -f https://llm.datasette.io/robots.txt --expand

You can display just the content for a specific fragment hash ID (or alias) using the llm fragments show command:

llm fragments show 993fd38d898d2b59fd2d16c811da5bdac658faa34f0f4d411edde7c17ebb0680

If you provide multiple fragments you will get back responses that used all of those fragments.

Filtering by prompts that used specific tools

You can filter for responses that used tools from specific fragments with the --tool/-T option:

llm logs -T simple_eval

This will match responses that involved a result from that tool. If the tool was not executed it will not be included in the filtered responses.

Pass --tool/-T multiple times for responses that used all of the specified tools.

Use the llm logs --tools flag to see all responses that involved at least one tool result, including from --functions:

llm logs --tools

Browsing data collected using schemas

The --schema X option can be used to view responses that used the specified schema, using any of the ways to specify a schema <#schemas-specify>:

llm logs --schema 'name, age int, bio'

This can be combined with --data and --data-array and --data-key to extract just the returned JSON data - consult the schemas documentation <#schemas-logs> for details.

Browsing logs using Datasette

You can also use Datasette <https://datasette.io/> to browse your logs like this:

datasette "$(llm logs path)"

Backing up your database

You can backup your logs to another file using the llm logs backup command:

llm logs backup /tmp/backup.db

This uses SQLite VACUUM INTO <https://sqlite.org/lang_vacuum.html#vacuum_with_an_into_clause> under the hood.

The message store

The logs.db database contains two generations of tables. Databases created by older versions of LLM recorded everything in a responses table, with companion tables such as prompt_attachments and tool_calls hanging off it. Current versions write to a set of content-addressed tables instead: threads, turns, messages and parts​. Content-addressed means that rows are identified by a hash of their content rather than an assigned id, so identical content is stored exactly once.

The legacy tables are read-only history now. The llm logs command merges the two generations: rows that only exist in the legacy responses table are combined with rows from the new tables, so history recorded by an older version stays visible after an upgrade. All new logging writes only the content-addressed tables.

Threads, turns, messages and parts

From the top down:

  • A thread is a conversation. It is a named pointer at the message at the head of that conversation, and its id is the conversation id displayed by llm logs​.
  • A turn is a single model call within a thread. It records everything specific to that call - which model answered, options, token counts, timings - and points at the messages that were its input and output.
  • A message is one entry in a conversation, with a role of system, user or assistant​. Each message links to its parent, forming a chain, and is identified by a hash of its content combined with that parent link.
  • A part is a piece of content within a message: text, reasoning, a tool call, a tool result or an attachment. A message's parts are ordered by their position​.

A worked example

Here is a two turn conversation, logged to a fresh database and then dumped. It was generated with a small scripted model that returns canned replies - every model plugin logs through the same code path, so rows written by a real model have exactly the same shape, but the canned replies keep this example deterministic.

messages and their parts:

user b2:d6b0cd4e7a65ea90423c50fadb3f5704
  parent: null
  part 0: type=text text='Suggest a name for a pet pelican' payload=null

assistant b2:0f2c02ad982050b623b7e034199c8c61
  parent: b2:d6b0cd4e7a65ea90423c50fadb3f5704
  part 0: type=text text='How about Percy? Pelicans suit a dignified name.' payload=null

user b2:c785dd6c77540150c2647f406cacc76f
  parent: b2:0f2c02ad982050b623b7e034199c8c61
  part 0: type=text text='Now one for a pet walrus' payload=null

assistant b2:a30a236e0d1b717c592e826d06e3c9d2
  parent: b2:c785dd6c77540150c2647f406cacc76f
  part 0: type=text text='Wallace. It pairs nicely with Percy.' payload=null

turns:

turn 01kf2rw8jj3nfd5t7w9y1a3c5e
  thread_id: 01kf2rw8jhv1x9c2m4p6q8s0tv
  parent_message_hash: b2:d6b0cd4e7a65ea90423c50fadb3f5704
  tip_message_hash:    b2:0f2c02ad982050b623b7e034199c8c61
  model: scripted

turn 01kf2rw8jkq7h9k2m4n6p8r0t2
  thread_id: 01kf2rw8jhv1x9c2m4p6q8s0tv
  parent_message_hash: b2:c785dd6c77540150c2647f406cacc76f
  tip_message_hash:    b2:a30a236e0d1b717c592e826d06e3c9d2
  model: scripted

thread:

thread 01kf2rw8jhv1x9c2m4p6q8s0tv
  name: Suggest a name for a pet pelican
  tip_message_hash: b2:a30a236e0d1b717c592e826d06e3c9d2

Things to notice:

  • The four messages form a chain: the first has a null parent and each subsequent message names the hash of the one before it.
  • The part N: lines show each part's storage columns. A part whose text is pure literal keeps it in the text column - raw, unescaped and never parsed, so text that happens to look like JSON is safe - with a null payload. The payload column holds any remaining structure as JSON: fragment references, tool call fields, provider metadata. The part's type lives only in the type column.
  • Each turn brackets one model call. Its parent_message_hash is the tip of the chain that was sent to the model - the last input message, usually that turn's user prompt - and its tip_message_hash is the chain tip after the model's reply was appended. The prompt and response that llm logs displays are derived by splitting the chain at the parent, rather than being stored a second time.
  • The thread's id is the conversation id, its name is derived from the first prompt and its tip_message_hash follows the head of the conversation as new turns are logged.
  • Turn and thread ids are ULIDs: sortable identifiers issued in time order. The ids shown here are illustrative, since fresh ones are generated on every run. The hashes are not - they depend only on the message content and its position in the chain, so replaying this conversation produces these exact four hashes.

Content addressing as a contract

A message's hash is calculated like this:

  1. Build the object {"parent": parent_hash, "message": message}, where parent_hash is the hash of the previous message in the chain (or null for the first message) and message is the message's dictionary representation - its role, its parts and any provider metadata.
  2. Serialize that object to canonical JSON: keys sorted, compact , and : separators with no extra whitespace, non-ASCII characters left unescaped.
  3. Hash the UTF-8 encoding of that string with BLAKE2b <https://en.wikipedia.org/wiki/BLAKE_(hash_function)> using a 16 byte digest, and prefix the hex digest with b2:​.

The b2: prefix names the algorithm that produced the hash, so any future change to it will be detectable.

Two design decisions matter here:

  • The hash covers resolved content. Fragment <#usage-fragments> references are expanded to their full text before hashing, and attachments are represented by the SHA-256 hash of their bytes together with their media type - the model sees the type, so identical bytes sent as image/png and as text/plain are different requests. An attachment supplied as a URL is hashed by that URL: the log records which URL was sent, not whatever it served that day. Attachments loaded from a filesystem path are stored by reference to that file rather than copied into the database, so their fidelity depends on the file staying put - LogStore.verify() re-reads the actual bytes when it re-derives every hash, and reports a changed or deleted file as a broken hash rather than letting it pass silently.
  • The parent hash participates in the hash. The same content appearing at a different point in a conversation is a different node. This is what makes two conversations that share a prefix collapse to shared rows, with no explicit comparison required: replaying the same messages produces the same hashes, and a hash that is already present needs nothing written.

A consequence of the second decision is that a stateless client - one that holds its own conversation history and re-sends the whole thing with every call - writes only the new tail on each request. It also makes forks cheap, as described next. Here the first conversation from the worked example is logged again, followed by a second conversation that starts with the same prompt and then diverges:

message rows after the first conversation: 4
message rows after both conversations:     6

rows added by the second conversation:

user b2:371ceec468c0ec797ac7042970992c0b
  parent: b2:0f2c02ad982050b623b7e034199c8c61

assistant b2:4ad19ddf94ea086aa9a8aa6fd8b0af05
  parent: b2:371ceec468c0ec797ac7042970992c0b

Two conversations of two turns each - eight messages sent to the model in total - produced six rows. The second conversation's first turn hashed to rows that were already present, so only its second turn was written, and the new user message's parent is the assistant reply both conversations share.

Forking and shared history

Because messages form a parent-linked tree, a conversation can fork: a new thread can point at any existing message and continue from there, sharing its entire history with the thread it came from until the two diverge. Nothing is copied when this happens. The threads.forked_from column records which thread a fork came from.

Shared rows cut both ways. Deleting a conversation is not the same as deleting its rows, because another thread may reach the same messages - removing them would silently corrupt that thread's history. For this reason LLM does not currently delete message rows at all; garbage collection of unreachable messages is deliberately left as future work.

Storage by reference

The hash of a message covers its resolved content, but storage is by reference. A text part whose content borrows from a fragment does not store a copy of that fragment. Instead of a filled text column its payload holds a text_ref list of fragment references and literal segments:

{"text_ref": [{"fragment": 1}, {"literal": "\nquestion about it"}]}

Here fragment 1 is an id in the existing fragments table. Reading the part concatenates the fragment content and the literal back together, reproducing the exact text that was hashed. Ask a hundred questions about a novel and the novel is stored once.

Attachments work the same way: the binary content lives in the attachments table, keyed by a SHA-256 hash of the bytes, and the part payload stores that id in place of the data.

The raw provider payload

The parts of a response are a normalized view of what the provider returned. The raw response.json() dictionary is also recorded in the turns.response_json column, storing details that have no part equivalent - usage breakdowns, system fingerprints, logprobs, and more.

The JSON is in a condensed form using condense-json <https://github.com/simonw/condense-json>​. This library allows values that are stored in the other database rows to be replaced in the JSON as special references such as {"$": "tool.NAME.description"}​.

Model plugins can contribute a dictionary of their own recurring boilerplate - the same idea as a zstandard custom dictionary - by defining a json_replacements class attribute. See the plugin author documentation <#advanced-model-plugins-json-replacements> for guidance on declaring these.

llm logs --json resolves the stored payload back to the original sen tby the provider as the response_json

Table by table

The full schema for these tables appears in the SQL schema section below.

  • messages - one row per unique message. hash is the content address described above, parent_hash links to the previous message in the chain and role is system, user or assistant​. provider_metadata holds any provider-specific data carried by the message; it participates in the hash.
  • parts - the content of each message, ordered by position​. When a part's text is stored inline in full it lives in the text column - raw and never parsed, so select text from parts reads as prose. Text that references fragments is stored in payload as text_ref instead. payload holds any remaining structure as JSON (fragment references, tool call fields, provider metadata), or NULL when the text column carries the whole part. type and tool_name are their own columns for direct filtering; the type never appears inside the payload.
  • part_attachments and part_fragments - junction tables recording which rows in attachments and fragments a part's payload references, in order.
  • threads - one row per conversation. id is the conversation id, tip_message_hash points at the current head of the conversation and forked_from records the thread a fork came from.
  • turns - one row per model call. parent_message_hash and tip_message_hash bracket the call's input and output as described above, and the remaining columns record provenance: model, options, schema, token counts, timings and the condensed raw provider payload in response_json​. Turn ids are ULIDs, in the same id space as legacy response ids, which is how the two generations of tables sort together in llm logs​.
  • turn_tools - which tool <#tools> definitions were available to a turn, referencing the tools table. For toolbox-derived tools, instance_id references the tool_instances row recording which configured instance provided them - so the tools list in llm logs shows that SQLite_query came from SQLite("mydb.db") before any call has run.
  • turn_fragments - which fragments a turn was given, with their kind (prompt or system) and order. Provenance lives here rather than on the shared message rows, and this table is what powers llm logs -f​.
  • turn_search - the searchable text of each turn: the literal prompt the user typed (fragment content excluded, via the text_ref literals described above) and the assistant's text output. An FTS5 index over this table, turn_search_fts, is what powers llm logs -q​. Derived from the stored parts when a turn is logged; a turn with no prompt or response text, such as a pure tool call, gets no row.
  • tool_instantiations - which configured toolbox <#python-api-toolbox> instance served a tool call, as a reference into the shared tool_instances table (each distinct configuration is stored once), keyed by (turn_id, tool_call_id) - call ids supplied by providers are not guaranteed unique across turns. Message rows are shared between conversations and so cannot carry this kind of local execution provenance; this table joins to the chain from outside it.

Querying the message store

These queries can be pasted into Datasette <https://datasette.io/> or sqlite3 against your logs.db​.

The database includes a message_tree view that renders every conversation tree as indented text, one row per message, depth-first with forks shown as siblings:

select * from message_tree

Its columns:

  • root_hash - the hash of the tree's root message, shared by every message in the tree. Filter or facet on this to isolate a single conversation and its forks.
  • datetime - when the message was first logged, derived from the earliest turn that recorded it (shared message rows carry no timestamp of their own).
  • message - the message's text, indented to show its depth in the tree. Text stored as fragment references is resolved back to the fragment content, and messages with no text show a placeholder such as [tool_result]​.
  • tools - names of any tools that were executed at that message, comma-separated.
  • message_hash and path - the message's own hash, and the sort key that produces the tree ordering. The rows only read as trees while sorted by path, so re-sorting by another column will scramble the indentation.

    with recursive msg as (
      select m.hash, m.parent_hash, m.role, m.rowid as rid,
        replace(coalesce(
          nullif(p.text, ''),
          (select f.content from part_fragments pf
           join fragments f on f.id = pf.fragment_id
           where pf.part_id = p.id
           order by pf."order" limit 1),
          '[' || coalesce(p.type, 'empty') || ']'
        ), char(10), ' ') as text,
        (select group_concat(p2.tool_name, ', ') from parts p2
         where p2.message_hash = m.hash and p2.type = 'tool_result'
           and p2.tool_name is not null) as tools
      from messages m
      left join parts p on p.message_hash = m.hash and p.position = 0
    ),
    tree as (
      select hash, text, tools, 0 as depth,
        printf('%012d', rid) as path, hash as root_hash
      from msg where parent_hash is null
      union all
      select msg.hash, msg.text, msg.tools, t.depth + 1,
        t.path || '/' || printf('%012d', msg.rid),
        t.root_hash
      from msg join tree t on msg.parent_hash = t.hash
    ),
    turn_chain as (
      select t.id as turn_id, t.datetime_utc, m.hash, m.parent_hash
      from turns t join messages m on m.hash = t.tip_message_hash
      union all
      select tc.turn_id, tc.datetime_utc, m.hash, m.parent_hash
      from turn_chain tc join messages m on m.hash = tc.parent_hash
    )
    select
      t.root_hash,
      strftime('%Y-%m-%d %H:%M:%S',
        (select min(tc.datetime_utc) from turn_chain tc where tc.hash = t.hash)
      ) as datetime,
      replace(hex(zeroblob(t.depth)), '00', '    ') || substr(t.text, 1, 60)
        as message,
      coalesce(t.tools, '') as tools,
      t.hash as message_hash,
      t.path
    from tree t
    order by t.path

Every turn that was given a specific fragment, via the turn_fragments provenance table - set :fragment_hash to a hash from llm fragments:

select turns.id, turns.model, turns.datetime_utc, turn_fragments.kind
from turns
join turn_fragments on turn_fragments.turn_id = turns.id
join fragments on fragments.id = turn_fragments.fragment_id
where fragments.hash = :fragment_hash
order by turns.id;

The most recently active conversations, with a count of their turns:

select
  threads.id,
  threads.name,
  count(turns.id) as num_turns,
  max(turns.datetime_utc) as last_used
from threads
left join turns on turns.thread_id = threads.id
group by threads.id
order by last_used desc
limit 10;

Logging from Python

The supported way to write to a log database from Python is the log_to_db() method on a response, which is also what plugins should call:

import llm
import sqlite_utils

db = sqlite_utils.Database("logs.db")
model = llm.get_model("gpt-5.5")
response = model.prompt("A short pelican fact")
print(response.text())
response.log_to_db(db)

log_to_db() takes a sqlite_utils.Database and records the response's thread, turn, messages, parts, fragments, attachments and tools in the content-addressed tables. It applies any outstanding migrations itself, so it is safe to call against a brand new database file or one created by an older version of LLM. The underlying LogStore class is internal and its API may change - log_to_db() and the table schema documented on this page are the supported interfaces.

SQL schema

Here's the SQL schema used by the logs.db database:

CREATE TABLE "conversations" (
  "id" TEXT PRIMARY KEY,
  "name" TEXT,
  "model" TEXT
);
CREATE TABLE "schemas" (
  "id" TEXT PRIMARY KEY,
  "content" TEXT
);
CREATE TABLE "responses" (
  "id" TEXT PRIMARY KEY,
  "model" TEXT,
  "prompt" TEXT,
  "system" TEXT,
  "prompt_json" TEXT,
  "options_json" TEXT,
  "response" TEXT,
  "response_json" TEXT,
  "conversation_id" TEXT REFERENCES "conversations"("id"),
  "duration_ms" INTEGER,
  "datetime_utc" TEXT,
  "input_tokens" INTEGER,
  "output_tokens" INTEGER,
  "token_details" TEXT,
  "schema_id" TEXT REFERENCES "schemas"("id"),
  "resolved_model" TEXT,
  "reasoning" TEXT
);
CREATE VIRTUAL TABLE "responses_fts" USING FTS5 (
  "prompt",
  "response",
  content="responses"
);
CREATE TABLE "attachments" (
  "id" TEXT PRIMARY KEY,
  "type" TEXT,
  "path" TEXT,
  "url" TEXT,
  "content" BLOB
);
CREATE TABLE "prompt_attachments" (
  "response_id" TEXT REFERENCES "responses"("id"),
  "attachment_id" TEXT REFERENCES "attachments"("id"),
  "order" INTEGER,
  PRIMARY KEY ("response_id",
  "attachment_id")
);
CREATE TABLE "fragments" (
  "id" INTEGER PRIMARY KEY,
  "hash" TEXT,
  "content" TEXT,
  "datetime_utc" TEXT,
  "source" TEXT
);
CREATE TABLE "fragment_aliases" (
  "alias" TEXT PRIMARY KEY,
  "fragment_id" INTEGER REFERENCES "fragments"("id")
);
CREATE TABLE "prompt_fragments" (
  "response_id" TEXT REFERENCES "responses"("id"),
  "fragment_id" INTEGER REFERENCES "fragments"("id"),
  "order" INTEGER,
  PRIMARY KEY ("response_id",
  "fragment_id",
  "order")
);
CREATE TABLE "system_fragments" (
  "response_id" TEXT REFERENCES "responses"("id"),
  "fragment_id" INTEGER REFERENCES "fragments"("id"),
  "order" INTEGER,
  PRIMARY KEY ("response_id",
  "fragment_id",
  "order")
);
CREATE TABLE "tools" (
  "id" INTEGER PRIMARY KEY,
  "hash" TEXT,
  "name" TEXT,
  "description" TEXT,
  "input_schema" TEXT,
  "plugin" TEXT
);
CREATE TABLE "tool_responses" (
  "tool_id" INTEGER REFERENCES "tools"("id"),
  "response_id" TEXT REFERENCES "responses"("id"),
  PRIMARY KEY ("tool_id",
  "response_id")
);
CREATE TABLE "tool_calls" (
  "id" INTEGER PRIMARY KEY,
  "response_id" TEXT REFERENCES "responses"("id"),
  "tool_id" INTEGER REFERENCES "tools"("id"),
  "name" TEXT,
  "arguments" TEXT,
  "tool_call_id" TEXT
);
CREATE TABLE "tool_results" (
  "id" INTEGER PRIMARY KEY,
  "response_id" TEXT REFERENCES "responses"("id"),
  "tool_id" INTEGER REFERENCES "tools"("id"),
  "name" TEXT,
  "output" TEXT,
  "tool_call_id" TEXT,
  "instance_id" INTEGER REFERENCES "tool_instances"("id"),
  "exception" TEXT
);
CREATE TABLE "tool_instances" (
  "id" INTEGER PRIMARY KEY,
  "plugin" TEXT,
  "name" TEXT,
  "arguments" TEXT
);
CREATE TABLE "tool_results_attachments" (
  "tool_result_id" INTEGER REFERENCES "tool_results"("id"),
  "attachment_id" TEXT REFERENCES "attachments"("id"),
  "order" INTEGER,
  PRIMARY KEY ("tool_result_id",
  "attachment_id")
);
CREATE TABLE "messages" (
  "hash" TEXT PRIMARY KEY,
  "parent_hash" TEXT REFERENCES "messages"("hash"),
  "role" TEXT,
  "provider_metadata" TEXT
);
CREATE TABLE "parts" (
  "id" INTEGER PRIMARY KEY,
  "message_hash" TEXT REFERENCES "messages"("hash"),
  "position" INTEGER,
  "type" TEXT,
  "tool_name" TEXT,
  "text" TEXT,
  "payload" TEXT
);
CREATE TABLE "part_attachments" (
  "part_id" INTEGER REFERENCES "parts"("id"),
  "attachment_id" TEXT REFERENCES "attachments"("id"),
  "order" INTEGER,
  PRIMARY KEY ("part_id",
  "attachment_id",
  "order")
);
CREATE TABLE "part_fragments" (
  "part_id" INTEGER REFERENCES "parts"("id"),
  "fragment_id" INTEGER REFERENCES "fragments"("id"),
  "order" INTEGER,
  PRIMARY KEY ("part_id",
  "fragment_id",
  "order")
);
CREATE TABLE "threads" (
  "id" TEXT PRIMARY KEY,
  "name" TEXT,
  "tip_message_hash" TEXT REFERENCES "messages"("hash"),
  "forked_from" TEXT REFERENCES "threads"("id"),
  "datetime_utc" TEXT
);
CREATE TABLE "turns" (
  "id" TEXT PRIMARY KEY,
  "thread_id" TEXT REFERENCES "threads"("id"),
  "parent_message_hash" TEXT REFERENCES "messages"("hash"),
  "tip_message_hash" TEXT REFERENCES "messages"("hash"),
  "model" TEXT,
  "resolved_model" TEXT,
  "options_json" TEXT,
  "schema_id" TEXT REFERENCES "schemas"("id"),
  "input_tokens" INTEGER,
  "output_tokens" INTEGER,
  "token_details" TEXT,
  "duration_ms" INTEGER,
  "datetime_utc" TEXT,
  "response_json" TEXT
);
CREATE TABLE "turn_tools" (
  "turn_id" TEXT REFERENCES "turns"("id"),
  "tool_id" INTEGER REFERENCES "tools"("id"),
  "instance_id" INTEGER REFERENCES "tool_instances"("id"),
  PRIMARY KEY ("turn_id",
  "tool_id")
);
CREATE TABLE "turn_fragments" (
  "turn_id" TEXT REFERENCES "turns"("id"),
  "fragment_id" INTEGER REFERENCES "fragments"("id"),
  "order" INTEGER,
  "kind" TEXT,
  PRIMARY KEY ("turn_id",
  "fragment_id",
  "kind",
  "order")
);
CREATE TABLE "turn_search" (
  "id" INTEGER PRIMARY KEY,
  "turn_id" TEXT REFERENCES "turns"("id"),
  "prompt" TEXT,
  "response" TEXT
);
CREATE VIRTUAL TABLE "turn_search_fts" USING FTS5 (
  "prompt",
  "response",
  content="turn_search"
);
CREATE TABLE "tool_instantiations" (
  "turn_id" TEXT REFERENCES "turns"("id"),
  "tool_call_id" TEXT,
  "instance_id" INTEGER REFERENCES "tool_instances"("id"),
  PRIMARY KEY ("turn_id",
  "tool_call_id")
);

responses_fts configures SQLite full-text search <https://www.sqlite.org/fts5.html> against the prompt and response columns in the responses table. turn_search_fts does the same for the turn_search table, which holds the searchable text of each turn in the content-addressed tables - together these are what llm logs -q queries.

strip-tags

strip-tags <https://github.com/simonw/strip-tags> is a command for stripping tags from HTML. This is useful when working with LLMs because HTML tags can use up a lot of your token budget.

Here's how to summarize the front page of the New York Times, by both stripping tags and filtering to just the elements with class="story-wrapper":

curl -s https://www.nytimes.com/ \
  | strip-tags .story-wrapper \
  | llm -s 'summarize the news'

llm, ttok and strip-tags—CLI tools for working with ChatGPT and other LLMs <https://simonwillison.net/2023/May/18/cli-tools-for-llms/> describes ways to use strip-tags in more detail.

ttok

ttok <https://github.com/simonw/ttok> is a command-line tool for counting OpenAI tokens. You can use it to check if input is likely to fit in the token limit for GPT 3.5 or GPT4:

cat my-file.txt | ttok
125

It can also truncate input down to a desired number of tokens:

ttok This is too many tokens -t 3
This is too

This is useful for truncating a large document down to a size where it can be processed by an LLM.

Symbex

Symbex <https://github.com/simonw/symbex> is a tool for searching for symbols in Python codebases. It's useful for extracting just the code for a specific problem and then piping that into LLM for explanation, refactoring or other tasks.

Here's how to use it to find all functions that match test*csv* and use those to guess what the software under test does:

symbex 'test*csv*' | \
  llm --system 'based on these tests guess what this tool does'

It can also be used to export symbols in a format that can be piped to llm embed-multi <#embeddings-cli-embed-multi> in order to create embeddings:

symbex '*' '*:*' --nl | \
  llm embed-multi symbols - \
  --format nl --database embeddings.db --store

For more examples see Symbex: search Python code for functions and classes, then pipe them into a LLM <https://simonwillison.net/2023/Jun/18/symbex/>​.

CLI reference

This page lists the --help output for all of the llm commands.

llm --help

Usage: llm [OPTIONS] COMMAND [ARGS]...

  Access Large Language Models from the command-line

  Documentation: https://llm.datasette.io/

  LLM can run models from many different providers. Consult the plugin directory
  for a list of available models:

  https://llm.datasette.io/en/stable/plugins/directory.html

  To get started with OpenAI, obtain an API key from them and:

      $ llm keys set openai
      Enter key: ...

  Then execute a prompt like this:

      llm 'Five outrageous names for a pet pelican'

  For a full list of prompting options run:

      llm prompt --help

Options:
  --version   Show the version and exit.
  -h, --help  Show this message and exit.

Commands:
  prompt*       Execute a prompt
  aliases       Manage model aliases
  chat          Hold an ongoing chat with a model.
  collections   View and manage collections of embeddings
  embed         Embed text and store or return the result
  embed-models  Manage available embedding models
  embed-multi   Store embeddings for multiple strings at once in the...
  fragments     Manage fragments that are stored in the database
  install       Install packages from PyPI into the same environment as LLM
  keys          Manage stored API keys for different models
  logs          Tools for exploring logged prompts and responses
  models        Manage available models
  openai        Commands for working with OpenAI and OpenAI-compatible APIs
  plugins       List installed plugins
  schemas       Manage stored schemas
  similar       Return top N similar IDs from a collection using cosine...
  templates     Manage stored prompt templates
  tools         Manage tools that can be made available to LLMs
  uninstall     Uninstall Python packages from the LLM environment

llm prompt --help

Usage: llm prompt [OPTIONS] [PROMPT]

  Execute a prompt

  Documentation: https://llm.datasette.io/en/stable/usage.html

  Examples:

      llm 'Capital of France?'
      llm 'Capital of France?' -m gpt-5.5
      llm 'Capital of France?' -s 'answer in Spanish'

  Multi-modal models can be called with attachments like this:

      llm 'Extract text from this image' -a image.jpg
      llm 'Describe' -a https://static.simonwillison.net/static/2024/pelicans.jpg
      cat image | llm 'describe image' -a -
      # With an explicit mimetype:
      cat image | llm 'describe image' --at - image/jpeg

  Structured output schemas:

  Use --schema to request one JSON object, or --schema-multi to request multiple
  objects returned in an "items" array. Both options accept a concise schema
  DSL. Define each field as NAME [TYPE]: DESCRIPTION, with the type and
  description both optional. Separate fields with commas:

      llm --schema 'name, age int, active bool' 'Invent a dog'

  Supported types are str, int, float and bool. The default is str and every
  listed field is required. Descriptions provide extra instructions to the
  model. Use one field per line if descriptions contain commas:

      llm --schema-multi '
      name: the dog's name
      age int: the dog's age in years
      bio: a short bio, no more than three sentences
      ' 'Invent three dogs'

  JSON Schema is also accepted.

  The -x/--extract option returns just the content of the first ``` fenced code
  block, if one is present. If none are present it returns the full response.

      llm 'JavaScript function for reversing a string' -x

Options:
  -s, --system TEXT               System prompt to use
  -m, --model TEXT                Model to use
  -d, --database FILE             Path to log database
  -q, --query TEXT                Use first model matching these strings
  -a, --attachment ATTACHMENT     Attachment path or URL or -
  --at, --attachment-type <TEXT TEXT>...
                                  Attachment with explicit mimetype,
                                  --at image.jpg image/jpeg
  -T, --tool TEXT                 Name of a tool to make available to the model
  --functions TEXT                Python code block or file path defining
                                  functions to register as tools
  --td, --tools-debug             Show full details of tool executions
  --ta, --tools-approve           Manually approve every tool execution
  --cl, --chain-limit INTEGER     How many chained tool responses to allow,
                                  default 5, set 0 for unlimited
  -o, --option <TEXT TEXT>...     key/value options for the model
  --options                       Show options for the selected model
  --schema TEXT                   Schema DSL, JSON schema, filepath or ID
  --schema-multi TEXT             Schema for multiple results
  -f, --fragment TEXT             Fragment (alias, URL, hash or file path) to
                                  add to the prompt
  --sf, --system-fragment TEXT    Fragment to add to system prompt
  -t, --template TEXT             Template to use; can be repeated to combine
                                  templates
  -p, --param <TEXT TEXT>...      Parameters for template
  --no-stream                     Do not stream output
  -n, --no-log                    Don't log to database
  --log                           Log prompt and response to the database
  -R, --hide-reasoning            Hide reasoning output
  -c, --continue                  Continue the most recent conversation.
  --cid, --conversation TEXT      Continue the conversation with the given ID.
  --key TEXT                      API key to use
  --save TEXT                     Save prompt with this template name
  --async                         Run prompt asynchronously
  -u, --usage                     Show token usage
  -x, --extract                   Extract first fenced code block
  --xl, --extract-last            Extract last fenced code block
  --json                          Output the response as JSON, same format as
                                  llm logs --json
  -h, --help                      Show this message and exit.

llm chat --help

Usage: llm chat [OPTIONS]

  Hold an ongoing chat with a model.

Options:
  -s, --system TEXT             System prompt to use
  -m, --model TEXT              Model to use
  -c, --continue                Continue the most recent conversation.
  --cid, --conversation TEXT    Continue the conversation with the given ID.
  -f, --fragment TEXT           Fragment (alias, URL, hash or file path) to add
                                to the prompt
  --sf, --system-fragment TEXT  Fragment to add to system prompt
  -t, --template TEXT           Template to use
  -p, --param <TEXT TEXT>...    Parameters for template
  -o, --option <TEXT TEXT>...   key/value options for the model
  -d, --database FILE           Path to log database
  --no-stream                   Do not stream output
  -R, --hide-reasoning          Hide reasoning output
  --key TEXT                    API key to use
  -T, --tool TEXT               Name of a tool to make available to the model
  --functions TEXT              Python code block or file path defining
                                functions to register as tools
  --td, --tools-debug           Show full details of tool executions
  --ta, --tools-approve         Manually approve every tool execution
  --cl, --chain-limit INTEGER   How many chained tool responses to allow,
                                default 5, set 0 for unlimited
  -h, --help                    Show this message and exit.

llm keys --help

Usage: llm keys [OPTIONS] COMMAND [ARGS]...

  Manage stored API keys for different models

Options:
  -h, --help  Show this message and exit.

Commands:
  list*  List names of all stored keys
  get    Return the value of a stored key
  path   Output the path to the keys.json file
  set    Save a key in the keys.json file

llm keys list --help

Usage: llm keys list [OPTIONS]

  List names of all stored keys

Options:
  -h, --help  Show this message and exit.

llm keys path --help

Usage: llm keys path [OPTIONS]

  Output the path to the keys.json file

Options:
  -h, --help  Show this message and exit.

llm keys get --help

Usage: llm keys get [OPTIONS] NAME

  Return the value of a stored key

  Example usage:

      export OPENAI_API_KEY=$(llm keys get openai)

Options:
  -h, --help  Show this message and exit.

llm keys set --help

Usage: llm keys set [OPTIONS] NAME

  Save a key in the keys.json file

  Example usage:

      $ llm keys set openai
      Enter key: ...

Options:
  --value TEXT  Value to set
  -h, --help    Show this message and exit.

llm logs --help

Usage: llm logs [OPTIONS] COMMAND [ARGS]...

  Tools for exploring logged prompts and responses

Options:
  -h, --help  Show this message and exit.

Commands:
  list*   Show logged prompts and their responses
  backup  Backup your logs database to this file
  off     Turn off logging for all prompts
  on      Turn on logging for all prompts
  path    Output the path to the logs.db file
  status  Show current status of database logging

llm logs path --help

Usage: llm logs path [OPTIONS]

  Output the path to the logs.db file

Options:
  -h, --help  Show this message and exit.

llm logs status --help

Usage: llm logs status [OPTIONS]

  Show current status of database logging

Options:
  -h, --help  Show this message and exit.

llm logs backup --help

Usage: llm logs backup [OPTIONS] PATH

  Backup your logs database to this file

Options:
  -h, --help  Show this message and exit.

llm logs on --help

Usage: llm logs on [OPTIONS]

  Turn on logging for all prompts

Options:
  -h, --help  Show this message and exit.

llm logs off --help

Usage: llm logs off [OPTIONS]

  Turn off logging for all prompts

Options:
  -h, --help  Show this message and exit.

llm logs list --help

Usage: llm logs list [OPTIONS]

  Show logged prompts and their responses

Options:
  -n, --count INTEGER         Number of entries to show - defaults to 3, use 0
                              for all
  -d, --database FILE         Path to log database
  -m, --model TEXT            Filter by model or model alias
  -q, --query TEXT            Search for logs matching this string
  -f, --fragment TEXT         Filter for prompts using these fragments
  -T, --tool TEXT             Filter for prompts with results from these tools
  --tools                     Filter for prompts with results from any tools
  --schema TEXT               Schema DSL, JSON schema, filepath or ID
  --schema-multi TEXT         JSON schema used for multiple results
  -l, --latest                Return latest results matching search query
  --data                      Output newline-delimited JSON data for schema
  --data-array                Output JSON array of data for schema
  --data-key TEXT             Return JSON objects from array in this key
  --data-ids                  Attach corresponding IDs to JSON objects
  -t, --truncate              Truncate long strings in output
  -s, --short                 Shorter YAML output with truncated prompts
  -u, --usage                 Include token usage
  -r, --response              Just output the last response
  -x, --extract               Extract first fenced code block
  --xl, --extract-last        Extract last fenced code block
  -c, --current               Show logs from the current conversation
  --cid, --conversation TEXT  Show logs for this conversation ID
  --id-gt TEXT                Return responses with ID > this
  --id-gte TEXT               Return responses with ID >= this
  --json                      Output logs as JSON
  -e, --expand                Expand fragments to show their content
  -h, --help                  Show this message and exit.

llm models --help

Usage: llm models [OPTIONS] COMMAND [ARGS]...

  Manage available models

Options:
  -h, --help  Show this message and exit.

Commands:
  list*    List available models
  default  Show or set the default model
  options  Manage default options for models

llm models list --help

Usage: llm models list [OPTIONS]

  List available models

Options:
  --options         Show options for each model, if available
  --async           List async models
  --schemas         List models that support schemas
  --tools           List models that support tools
  --json            Output as JSON
  -q, --query TEXT  Search for models matching these strings
  -m, --model TEXT  Specific model IDs
  -h, --help        Show this message and exit.

llm models default --help

Usage: llm models default [OPTIONS] [MODEL]

  Show or set the default model

Options:
  -h, --help  Show this message and exit.

llm models options --help

Usage: llm models options [OPTIONS] COMMAND [ARGS]...

  Manage default options for models

Options:
  -h, --help  Show this message and exit.

Commands:
  list*  List default options for all models
  clear  Clear default option(s) for a model
  set    Set a default option for a model
  show   List default options set for a specific model

llm models options list --help

Usage: llm models options list [OPTIONS]

  List default options for all models

  Example usage:

      llm models options list

Options:
  -h, --help  Show this message and exit.

llm models options show --help

Usage: llm models options show [OPTIONS] MODEL

  List default options set for a specific model

  Example usage:

      llm models options show gpt-4.1

Options:
  -h, --help  Show this message and exit.

llm models options set --help

Usage: llm models options set [OPTIONS] MODEL KEY VALUE

  Set a default option for a model

  Example usage:

      llm models options set gpt-4.1 temperature 0.5

Options:
  -h, --help  Show this message and exit.

llm models options clear --help

Usage: llm models options clear [OPTIONS] MODEL [KEY]

  Clear default option(s) for a model

  Example usage:

      llm models options clear gpt-4.1
      # Or for a single option
      llm models options clear gpt-4.1 temperature

Options:
  -h, --help  Show this message and exit.

llm templates --help

Usage: llm templates [OPTIONS] COMMAND [ARGS]...

  Manage stored prompt templates

Options:
  -h, --help  Show this message and exit.

Commands:
  list*    List available prompt templates
  edit     Edit the specified prompt template using the default $EDITOR
  loaders  Show template loaders registered by plugins
  path     Output the path to the templates directory
  show     Show the specified prompt template

llm templates list --help

Usage: llm templates list [OPTIONS]

  List available prompt templates

Options:
  -h, --help  Show this message and exit.

llm templates show --help

Usage: llm templates show [OPTIONS] NAME

  Show the specified prompt template

Options:
  -h, --help  Show this message and exit.

llm templates edit --help

Usage: llm templates edit [OPTIONS] NAME

  Edit the specified prompt template using the default $EDITOR

Options:
  -h, --help  Show this message and exit.

llm templates path --help

Usage: llm templates path [OPTIONS]

  Output the path to the templates directory

Options:
  -h, --help  Show this message and exit.

llm templates loaders --help

Usage: llm templates loaders [OPTIONS]

  Show template loaders registered by plugins

Options:
  -h, --help  Show this message and exit.

llm schemas --help

Usage: llm schemas [OPTIONS] COMMAND [ARGS]...

  Manage stored schemas

Options:
  -h, --help  Show this message and exit.

Commands:
  list*  List stored schemas
  dsl    Convert LLM's schema DSL to a JSON schema
  show   Show a stored schema

llm schemas list --help

Usage: llm schemas list [OPTIONS]

  List stored schemas

Options:
  -d, --database FILE  Path to log database
  -q, --query TEXT     Search for schemas matching this string
  --full               Output full schema contents
  --json               Output as JSON
  --nl                 Output as newline-delimited JSON
  -h, --help           Show this message and exit.

llm schemas show --help

Usage: llm schemas show [OPTIONS] SCHEMA_ID

  Show a stored schema

Options:
  -d, --database FILE  Path to log database
  -h, --help           Show this message and exit.

llm schemas dsl --help

Usage: llm schemas dsl [OPTIONS] INPUT

  Convert LLM's schema DSL to a JSON schema

      llm schema dsl 'name, age int, bio: their bio'

Options:
  --multi     Wrap in an array
  -h, --help  Show this message and exit.

llm tools --help

Usage: llm tools [OPTIONS] COMMAND [ARGS]...

  Manage tools that can be made available to LLMs

Options:
  -h, --help  Show this message and exit.

Commands:
  list*  List available tools, optionally including tools supported by a model

llm tools list --help

Usage: llm tools list [OPTIONS] [TOOL_DEFS]...

  List available tools, optionally including tools supported by a model

Options:
  --json            Output as JSON
  -m, --model TEXT  List tools supported by this model
  --functions TEXT  Python code block or file path defining functions to
                    register as tools
  -h, --help        Show this message and exit.

llm aliases --help

Usage: llm aliases [OPTIONS] COMMAND [ARGS]...

  Manage model aliases

Options:
  -h, --help  Show this message and exit.

Commands:
  list*   List current aliases
  path    Output the path to the aliases.json file
  remove  Remove an alias
  set     Set an alias for a model

llm aliases list --help

Usage: llm aliases list [OPTIONS]

  List current aliases

Options:
  --json      Output as JSON
  -h, --help  Show this message and exit.

llm aliases set --help

Usage: llm aliases set [OPTIONS] ALIAS [MODEL_ID]

  Set an alias for a model

  Example usage:

      llm aliases set luna gpt-5.6-luna

  Alternatively you can omit the model ID and specify one or more -q options.
  The first model matching all of those query strings will be used.

      llm aliases set luna -q gpt -q luna

Options:
  -q, --query TEXT  Set alias for model matching these strings
  -h, --help        Show this message and exit.

llm aliases remove --help

Usage: llm aliases remove [OPTIONS] ALIAS

  Remove an alias

  Example usage:

      $ llm aliases remove turbo

Options:
  -h, --help  Show this message and exit.

llm aliases path --help

Usage: llm aliases path [OPTIONS]

  Output the path to the aliases.json file

Options:
  -h, --help  Show this message and exit.

llm fragments --help

Usage: llm fragments [OPTIONS] COMMAND [ARGS]...

  Manage fragments that are stored in the database

  Fragments are reusable snippets of text that are shared across multiple
  prompts.

Options:
  -h, --help  Show this message and exit.

Commands:
  list*    List current fragments
  loaders  Show fragment loaders registered by plugins
  remove   Remove a fragment alias
  set      Set an alias for a fragment
  show     Display the fragment stored under an alias or hash

llm fragments list --help

Usage: llm fragments list [OPTIONS]

  List current fragments

Options:
  -q, --query TEXT  Search for fragments matching these strings
  --aliases         Show only fragments with aliases
  --json            Output as JSON
  -h, --help        Show this message and exit.

llm fragments set --help

Usage: llm fragments set [OPTIONS] ALIAS FRAGMENT

  Set an alias for a fragment

  Accepts an alias and a file path, URL, hash or '-' for stdin

  Example usage:

      llm fragments set mydocs ./docs.md

Options:
  -h, --help  Show this message and exit.

llm fragments show --help

Usage: llm fragments show [OPTIONS] ALIAS_OR_HASH

  Display the fragment stored under an alias or hash

      llm fragments show mydocs

Options:
  -h, --help  Show this message and exit.

llm fragments remove --help

Usage: llm fragments remove [OPTIONS] ALIAS

  Remove a fragment alias

  Example usage:

      llm fragments remove docs

Options:
  -h, --help  Show this message and exit.

llm fragments loaders --help

Usage: llm fragments loaders [OPTIONS]

  Show fragment loaders registered by plugins

Options:
  -h, --help  Show this message and exit.

llm plugins --help

Usage: llm plugins [OPTIONS]

  List installed plugins

Options:
  --all        Include built-in default plugins
  --hook TEXT  Filter for plugins that implement this hook
  -h, --help   Show this message and exit.

llm install --help

Usage: llm install [OPTIONS] [PACKAGES]...

  Install packages from PyPI into the same environment as LLM

Options:
  -U, --upgrade        Upgrade packages to latest version
  -e, --editable TEXT  Install a project in editable mode from this path
  --force-reinstall    Reinstall all packages even if they are already up-to-
                       date
  --no-cache-dir       Disable the cache
  --pre                Include pre-release and development versions
  -h, --help           Show this message and exit.

llm uninstall --help

Usage: llm uninstall [OPTIONS] PACKAGES...

  Uninstall Python packages from the LLM environment

Options:
  -y, --yes   Don't ask for confirmation
  -h, --help  Show this message and exit.

llm embed --help

Usage: llm embed [OPTIONS] [COLLECTION] [ID]

  Embed text and store or return the result

Options:
  -i, --input PATH                File to embed
  -m, --model TEXT                Embedding model to use
  --key TEXT                      API key to use
  --store                         Store the text itself in the database
  -d, --database FILE
  -c, --content TEXT              Content to embed
  --binary                        Treat input as binary data
  --metadata TEXT                 JSON object metadata to store
  -f, --format [json|blob|base64|hex]
                                  Output format
  -h, --help                      Show this message and exit.

llm embed-multi --help

Usage: llm embed-multi [OPTIONS] COLLECTION [INPUT_PATH]

  Store embeddings for multiple strings at once in the specified collection.

  Input data can come from one of three sources:

  1. A CSV, TSV, JSON or JSONL file:
     - CSV/TSV: First column is ID, remaining columns concatenated as content
     - JSON: Array of objects with "id" field and content fields
     - JSONL: Newline-delimited JSON objects

     Examples:
       llm embed-multi docs input.csv
       cat data.json | llm embed-multi docs -
       llm embed-multi docs input.json --format json

  2. A SQL query against a SQLite database:
     - First column returned is used as ID
     - Other columns concatenated to form content

     Examples:
       llm embed-multi docs --sql "SELECT id, title, body FROM posts"
       llm embed-multi docs --attach blog blog.db --sql "SELECT id, content FROM blog.posts"

  3. Files in directories matching glob patterns:
     - Each file becomes one embedding
     - Relative file paths become IDs

     Examples:
       llm embed-multi docs --files docs '**/*.md'
       llm embed-multi images --files photos '*.jpg' --binary
       llm embed-multi texts --files texts '*.txt' --encoding utf-8 --encoding latin-1

Options:
  --format [json|csv|tsv|nl]   Format of input file - defaults to auto-detect
  --files <DIRECTORY TEXT>...  Embed files in this directory - specify directory
                               and glob pattern
  --encoding TEXT              Encodings to try when reading --files
  --binary                     Treat --files as binary data
  --sql TEXT                   Read input using this SQL query
  --attach <TEXT FILE>...      Additional databases to attach - specify alias
                               and file path
  --batch-size INTEGER         Batch size to use when running embeddings
  --prefix TEXT                Prefix to add to the IDs
  -m, --model TEXT             Embedding model to use
  --key TEXT                   API key to use
  --prepend TEXT               Prepend this string to all content before
                               embedding
  --store                      Store the text itself in the database
  -d, --database FILE
  -h, --help                   Show this message and exit.

llm similar --help

Usage: llm similar [OPTIONS] COLLECTION [ID]

  Return top N similar IDs from a collection using cosine similarity.

  Example usage:

      llm similar my-collection -c "I like cats"

  Or to find content similar to a specific stored ID:

      llm similar my-collection 1234

Options:
  -i, --input PATH      File to embed for comparison
  -c, --content TEXT    Content to embed for comparison
  --binary              Treat input as binary data
  -n, --number INTEGER  Number of results to return
  -p, --plain           Output in plain text format
  -d, --database FILE
  --prefix TEXT         Just IDs with this prefix
  -h, --help            Show this message and exit.

llm embed-models --help

Usage: llm embed-models [OPTIONS] COMMAND [ARGS]...

  Manage available embedding models

Options:
  -h, --help  Show this message and exit.

Commands:
  list*    List available embedding models
  default  Show or set the default embedding model

llm embed-models list --help

Usage: llm embed-models list [OPTIONS]

  List available embedding models

Options:
  -q, --query TEXT  Search for embedding models matching these strings
  -h, --help        Show this message and exit.

llm embed-models default --help

Usage: llm embed-models default [OPTIONS] [MODEL]

  Show or set the default embedding model

Options:
  --remove-default  Reset to specifying no default model
  -h, --help        Show this message and exit.

llm collections --help

Usage: llm collections [OPTIONS] COMMAND [ARGS]...

  View and manage collections of embeddings

Options:
  -h, --help  Show this message and exit.

Commands:
  list*   View a list of collections
  delete  Delete the specified collection
  path    Output the path to the embeddings database

llm collections path --help

Usage: llm collections path [OPTIONS]

  Output the path to the embeddings database

Options:
  -h, --help  Show this message and exit.

llm collections list --help

Usage: llm collections list [OPTIONS]

  View a list of collections

Options:
  -d, --database FILE  Path to embeddings database
  --json               Output as JSON
  -h, --help           Show this message and exit.

llm collections delete --help

Usage: llm collections delete [OPTIONS] COLLECTION

  Delete the specified collection

  Example usage:

      llm collections delete my-collection

Options:
  -d, --database FILE  Path to embeddings database
  -h, --help           Show this message and exit.

llm openai --help

Usage: llm openai [OPTIONS] COMMAND [ARGS]...

  Commands for working with OpenAI and OpenAI-compatible APIs

Options:
  -h, --help  Show this message and exit.

Commands:
  endpoint  Run against an OpenAI-compatible endpoint without logging.
  models    List models available to you from the OpenAI API

llm openai endpoint --help

Usage: llm openai endpoint [OPTIONS] URL [PROMPT]

  Run against an OpenAI-compatible endpoint without logging.

  PROMPT or stdin is executed once. If neither is provided, wait for input on
  stdin. Use --chat to start an interactive chat. Templates run once by default;
  use --chat to apply one interactively. Use --models to list the available
  model IDs without running a prompt.

Options:
  -m, --model TEXT                Model ID (required unless --models or provided
                                  by template)
  -s, --system TEXT               System prompt to use
  -t, --template TEXT             Template to use
  -p, --param <TEXT TEXT>...      Parameters for template
  -o, --option <TEXT TEXT>...     key/value options for the model
  --schema TEXT                   Schema DSL, JSON schema, filepath or ID
  --schema-multi TEXT             JSON schema to use for multiple results
  -a, --attachment ATTACHMENT     Attachment path or URL or -
  --at, --attachment-type <TEXT TEXT>...
                                  Attachment with explicit mimetype,
                                  --at image.jpg image/jpeg
  -T, --tool TEXT                 Name of a tool to make available to the model
  --functions TEXT                Python code block or file path defining
                                  functions to register as tools
  --td, --tools-debug             Show full details of tool executions
  --ta, --tools-approve           Manually approve every tool execution
  --cl, --chain-limit INTEGER     How many chained tool responses to allow,
                                  default 5, set 0 for unlimited
  --key TEXT                      API key or stored key alias to send
  -H, --header <TEXT TEXT>...     Additional HTTP header
  --responses                     Use the Responses API instead of Chat
                                  Completions
  --chat                          Start an interactive chat
  --models                        List model IDs from the endpoint and exit
  --no-stream                     Do not stream output
  -R, --hide-reasoning            Hide reasoning output
  -h, --help                      Show this message and exit.

llm openai models --help

Usage: llm openai models [OPTIONS]

  List models available to you from the OpenAI API

Options:
  --json      Output as JSON
  --key TEXT  OpenAI API key
  -h, --help  Show this message and exit.

Contributing

To contribute to this tool, first checkout the code. Then run the tests with uv run:

cd llm
uv run pytest

You can run your development copy of llm using uv run as well:

uv run llm --help

Updating recorded HTTP API interactions and associated snapshots

This project uses pytest-recording <https://github.com/kiwicom/pytest-recording> to record OpenAI API responses for some of the tests, and syrupy <https://github.com/syrupy-project/syrupy> to capture snapshots of their results.

If you add a new test that calls the API you can capture the API response and snapshot like this:

PYTEST_OPENAI_API_KEY="$(llm keys get openai)" uv run pytest --record-mode once --snapshot-update

Then review the new snapshots in tests/__snapshots__/ to make sure they look correct.

Debugging tricks

The default OpenAI plugin has a debugging mechanism for showing the exact requests and responses that were sent to the OpenAI API.

Set the LLM_OPENAI_SHOW_RESPONSES environment variable like this:

LLM_OPENAI_SHOW_RESPONSES=1 uv run llm -m chatgpt 'three word slogan for an otter-run bakery'

This will output details of the API requests and responses to the console.

Use --no-stream to see a more readable version of the body that avoids streaming the response:

LLM_OPENAI_SHOW_RESPONSES=1 uv run llm -m chatgpt --no-stream \
  'three word slogan for an otter-run bakery'

Documentation

Documentation for this project uses MyST <https://myst-parser.readthedocs.io/> - it is written in Markdown and rendered using Sphinx.

To build the documentation locally, run the following:

just docs

This will start a live preview server, using sphinx-autobuild <https://pypi.org/project/sphinx-autobuild/>​.

The CLI --help examples in the documentation are managed using Cog <https://github.com/nedbat/cog>​. Update those files like this:

just cog

You'll need Just <https://github.com/casey/just> installed to run these commands.

Release process

To release a new version:

  1. Update docs/changelog.md with the new changes.
  2. Update the version number in pyproject.toml
  3. Run just cog to update docs/fragments.md with the new version number.
  4. Create a GitHub release <https://github.com/simonw/llm/releases/new> for the new version.
  5. Wait for the package to push to PyPI and then...
  6. Run the regenerate.yaml <https://github.com/simonw/homebrew-llm/actions/workflows/regenerate.yaml> workflow to update the Homebrew tap to the latest version.

Changelog

0.34 (2026-09-02)

New features:

  • llm logs --usage Markdown output now includes the response duration in milliseconds and as a human-readable duration. llm logs --short includes a new duration_ms field. #1653 <https://github.com/simonw/llm/issues/1653>

Bug fixes:

0.33 (2026-08-22)

New features:

Bug fixes:

0.32.1 (2026-08-21)

This version pins LLM to use OpenAI Python versions less than v3.0.0 <https://github.com/openai/openai-python/releases#release-v3.0.0>, ensuring fresh LLM installations work without needing to also install an extra httpx dependency. #1630 <https://github.com/simonw/llm/pull/1630>

0.32 (2026-08-04)

LLM 0.32 is a major, backwards-compatible update to the way prompts, responses, tools and logs are represented. It adds structured messages and parts throughout the Python API, adopts the OpenAI Responses API for reasoning-capable models, substantially expands control over pausable and resumable tool loops and introduces a new content-addressed SQLite logging schema. Reasoning traces are now displayed on standard error by the llm command, for models that support them.

Structured messages and richer responses

Prompt inputs and model outputs are now represented as lists of Message objects, each containing typed Part objects for text, reasoning, tool calls, tool results and attachments.

  • New messages= keyword argument <#python-api-messages> on the prompt, conversation and chain APIs, including their asynchronous equivalents. For example, model.prompt(messages=[llm.user("Hello"), llm.assistant("Hi!"), llm.user("What can you do?")])​. Existing prompt=, system=, attachments= and tool_results= arguments continue to work and are converted into the same structured representation.
  • New structured streaming methods <#python-api-messages> response.stream_events() and response.astream_events() expose mixed streams of text, reasoning, tool calls and tool results. Iterating over a response directly continues to yield text strings.
  • response.messages() returns the assembled structured output. response.reply() continues from any response and can automatically execute pending tool calls before the next turn.
  • response.to_dict() and Response.from_dict() provide JSON-safe persistence of complete turns, including reasoning and provider metadata, with matching TypedDict definitions in the new llm.serialization module.
  • response.prompt.messages is now the canonical record of exactly what was sent to the model, including the full preceding conversation chain.

These APIs were introduced in 0.32a0​. They are described in the Advanced model plugins <#advanced-model-plugins> documentation.

OpenAI Responses API and reasoning

  • Most reasoning-capable OpenAI models now use the /v1/responses endpoint by default, enabling interleaved reasoning across tool calls. The existing Chat Completions classes remain available, and -o chat_completions 1 selects that older path for an individual prompt. See 0.32a2 for the full list of affected models.
  • OpenAI Responses API models now provide WebSearch <#openai-models-web-search> and CodeInterpreter <#openai-models-code-interpreter> server-side tools, available from the CLI using -T WebSearch or -T 'CodeInterpreter(memory_limit="4g")'​.
  • Visible reasoning summaries <#python-api-messages-reasoning> are streamed to standard error by llm prompt and llm chat​. Use -R/--hide-reasoning or the new hide_reasoning=True Python argument to hide them. Encrypted reasoning metadata is preserved for subsequent turns.
  • The default model for users who have not selected one is now GPT-5.6 Luna <https://developers.openai.com/api/docs/models/gpt-5.6-luna>, replacing GPT-4o mini. New built-in models include gpt-5.6-sol, gpt-5.6-terra and gpt-5.6-luna; models that are no longer available from OpenAI have been removed. See 0.32rc1 and 0.32rc2 for details.
  • New llm openai endpoint <#openai-endpoint> command runs prompts and chats, or lists models, against an arbitrary OpenAI-compatible endpoint without configuring it first. These calls are not logged.
  • OpenAI models now support a service_tier option. Use -o service_tier fast for faster responses at a higher price, or -o service_tier flex for slower, cheaper processing on supported models. See Fast mode and service tiers <#openai-models-service-tier>​. #1585 <https://github.com/simonw/llm/pull/1585>
  • New llm -m model --options flag lists the options supported by a model. The Python prompt APIs now accept an explicit options= dictionary <#python-api-model-options> as well as the previous keyword-argument form.

More controllable tool loops

  • Every tool call now has a unique tool_call_id, synthesized when the provider does not supply one. Tool implementations can accept an llm_tool_call parameter <#python-api-tools-llm-tool-call> to inspect the current call and its ID.
  • Tools can raise llm.PauseChain <#python-api-tools-pause> to pause execution for human approval or another external event. Chains can later resume from a message history ending in unresolved tool calls <#python-api-tools-resume>, without repeating calls that already have results.
  • Conversations that use configured tools <#usage-tools> can be continued with llm -c or llm chat -c without repeating the toolbox configuration.
  • llm tools now shows constructor signatures and docstrings for dynamic toolboxes <#python-api-tools-dynamic>​. Passing a toolbox specification instantiates it and lists its runtime-generated tools, while llm tools --json identifies dynamic toolboxes with a "dynamic" boolean. #1580 <https://github.com/simonw/llm/issues/1580>
  • Models can now declare the server-side tools they support <#advanced-model-plugins-server-side-tools> using the instance-level supported_server_side_tools property and the new llm.ServerSideTool base class. Server-executed calls and results are captured as structured message parts, and llm -c restores configured server-side tools for continued conversations. #1592 <https://github.com/simonw/llm/issues/1592>, #1593 <https://github.com/simonw/llm/pull/1593>
  • llm tools -m MODEL <#usage-tools> lists the server-side tools supported by that model. llm models --json returns model aliases, capability flags, attachment types and server-side tools, with option schemas included when combined with --options​.
  • OpenAI-compatible Responses endpoints <#openai-endpoint> can use provider-specific server-side tools with ServerSideTool(spec={...}), including OpenRouter's web search implementation.

See 0.32a3 for more detail on pausing, resuming and inspecting tool calls.

New SQLite logging schema

LLM now logs prompts and responses using a new schema built around threads, turns and a content-addressed message store​. Existing records in the legacy responses table are left untouched, and llm logs combines both generations of data. You can create a backup <#logging-backup> before upgrading using:

llm logs backup logs-backup.db
  • Messages are stored once and referenced by their content hash, preserving structured text, reasoning, attachments and tool activity without duplicating repeated conversation history. See the message store documentation <#logging-message-store>​.
  • Raw provider payloads are stored in turns.response_json, condensed <#logging-message-store-response-json> using condense-json <https://github.com/simonw/condense-json>​. llm logs --json expands them back to their original shape, and LogStore.turn_response_json(turn_id) returns them from Python. #1586 <https://github.com/simonw/llm/pull/1586>
  • Model plugins can define json_replacements <#advanced-model-plugins-json-replacements> dictionaries to further improve payload compression.
  • Full-text search <#logging-search>, model <#logging-filter-model> and tool filters <#logging-filter-tools>, and conversation views <#logging-conversation> work across both the legacy and new tables. Logs now record which configured toolbox instance supplied each tool.
  • New Response.log_to_db() <#logging-message-store-python> Python API writes a response to a logs database. llm prompt --json outputs the same structured representation as llm logs --json, even when persistent logging is disabled.
  • New message_tree SQL view <#logging-message-store-queries> renders conversation threads as indented text outlines for direct SQL exploration.
  • LLM now requires sqlite-utils 4.0 <https://sqlite-utils.datasette.io/en/stable/changelog.html#v4-0> or higher and no longer depends on sqlite-migrate​.

See 0.32rc1 for the detailed migration notes and complete list of logging changes.

Fixes since 0.32rc2

  • Fixed streamed OpenAI Responses API calls recording two different ciphertexts of the same reasoning: the part's encrypted_content was harvested from the response.output_item.done event while response_json came from response.completed, and OpenAI encrypts per event. Reasoning metadata is now re-emitted from the final payload, so both records agree on one blob.
  • Attachments loaded from URLs now follow up to three redirects when detecting their content type or fetching their bytes. Thanks, Ojas Sharma <https://github.com/ojassharma7>​. #1046 <https://github.com/simonw/llm/issues/1046>, #1579 <https://github.com/simonw/llm/pull/1579>
  • Fixed a bug where llm openai endpoint --schema was ignored if the selected template also defined a schema. Thanks, ikatyal2110 <https://github.com/ikatyal2110>​. #1588 <https://github.com/simonw/llm/pull/1588>
  • llm logs status now counts records in the new threads and turns tables, with legacy conversation and response counts shown separately when present.
  • Response.to_dict() now executes an unconsumed synchronous response before serializing it instead of producing an empty assistant message list.
  • Response.from_dict() now restores pending client-side tool calls so they can be inspected, executed or continued using response.reply(tools=[...])​.
  • Response.reply() now correctly passes attachments returned by tools <#python-api-tools-attachments> to the next model call, for both synchronous and asynchronous responses.

0.32rc2 (2026-07-30)

0.32rc1 (2026-07-30)

This release candidate for 0.32 introduces a new database schema for logging prompts and responses that captures full details of the interaction with the underlying LLM, and de-duplicates those records using a content-addressed message store​.

Upgrading to this RC will create those new tables and start logging to them. Existing data in the responses table will be left unaffected, and the logs command will read from both old and new tables. New interactions will only be written to the new tables.

You can create a backup of your logs database prior to upgrading using:

llm logs backup logs-backup.db

Changes to SQLite logging

  • See the message store documentation <#logging-message-store> for details of the new logging schema.
  • llm prompt logs are now written to a new set of tables, not the legacy tables.
  • New documented Response.log_to_db() <#logging-message-store-python> Python API for writing to a SQLite logs database.
  • llm logs now reads both generations of log tables: history recorded by older versions of LLM in the legacy responses table is merged into the output alongside new turns, with rows from the dual-write era deduplicated by id. The -m, -c, -f, -T, --tools and --schema filters work across both. #1562 <https://github.com/simonw/llm/pull/1562>
  • Raw provider payloads (the old prompt_json and response_json columns) are no longer persisted - the stored message chain is the record of what was sent and returned. This means data that only ever lived in those raw payloads is no longer stored, notably the log probabilities returned by OpenAI completion models with -o logprobs​.
  • llm logs -q full-text search works against the new log tables. Search covers the prompt text you typed and the model's text responses - system prompts, fragment contents, tool activity and reasoning traces are excluded from the index. See Searching the logs <#logging-search>​.
  • llm logs now shows which configured toolbox instance provided each tool - in the tools list for a prompt and on each tool result, so a SQLite_query result records that it ran against SQLite("mydb.db")​.
  • New message_tree SQL view <#logging-message-store-queries> that renders each conversation thread as an indented text outline, for exploring the message store directly with SQL. #1562 <https://github.com/simonw/llm/pull/1562>

Other changes

  • New OpenAI models: gpt-5.6-sol, gpt-5.6-terra and gpt-5.6-luna​.
  • Removed OpenAI models that are no longer available via the OpenAI API: chatgpt-4o-latest, the gpt-4o and gpt-4o-mini audio preview models, gpt-4-32k, gpt-4-1106-preview, gpt-4-0125-preview, the gpt-4.5 preview models, o1-preview, o1-mini and gpt-5.1-chat-latest​. #1553 <https://github.com/simonw/llm/issues/1553>
  • Continuing a conversation that used a configured toolbox now works: llm -c and llm chat -c reconstruct each toolbox instance from its recorded configuration, so a conversation started with -T 'Datasette("https://datasette.io/content")' can be continued without repeating the -T option.
  • New llm prompt --json option which outputs a JSON array describing the prompt and the response, in the same format as llm logs --json​. This works even with --no-log or logging turned off, in which case the response is logged to a temporary in-memory database to build the JSON. #1566 <https://github.com/simonw/llm/pull/1566>
  • New response.execute_tool_call(tool_call) method (awaitable on async responses) that executes a single tool call and returns its ToolResult​. This is designed for plugins wrapping provider SDKs that orchestrate the tool loop themselves, described in the advanced model plugins documentation <#advanced-model-plugins-execute-tool-call>​.
  • Documentation for the responses: true setting in extra-openai-models.yaml, which opts a custom OpenAI model into the Responses API instead of Chat Completions. See Adding more OpenAI models <#openai-extra-models>​.
  • Fixed a bug where the system prompt was omitted from the pre-computed prompt.messages on the first turn of a conversation, so models that build their request from that message list never received it. Thanks, Niall Smart <https://github.com/niallsmart>​. #1478 <https://github.com/simonw/llm/issues/1478>
  • Fixed a bug on Windows where a fragment argument holding an absolute path such as C:\Users\demo\notes.txt was mistaken for a reference to a c: fragment loader plugin. Fragment arguments that match an existing file path now always resolve as files. #1563 <https://github.com/simonw/llm/issues/1563>
  • LLM now requires sqlite-utils 4.0 <https://sqlite-utils.datasette.io/en/stable/changelog.html#v4-0> or higher.

0.31.1 (2026-07-09)

0.32a3 (2026-06-09)

Driven by the needs of Datasette Agent <https://github.com/datasette/datasette-agent>'s human-in-the-loop ask_user() feature, made the following improvements to how tool calls work:

  • Tool implementations can declare a parameter named llm_tool_call in order to be passed the llm.ToolCall object for the current invocation. This allows them to access the current llm_tool_call.tool_call_id​. See Accessing the tool call from inside a tool <#python-api-tools-llm-tool-call>​. #1480 <https://github.com/simonw/llm/pull/1480>
  • Every tool call is now guaranteed a unique tool_call_id - providers that do not supply one get a synthesized tc_-prefixed ULID. #1481 <https://github.com/simonw/llm/pull/1481>
  • Tools can raise a llm.PauseChain exception to cleanly pause the tool chain, useful for things like waiting for human approval. The exception propagates to the caller with ​.tool_call and ​.tool_results (completed sibling results) attached, and no model call is made with a placeholder result. See Pausing a chain from inside a tool <#python-api-tools-pause>​. #1482 <https://github.com/simonw/llm/pull/1482>
  • Failure semantics for concurrent tool execution: async sibling tool calls always run to completion before a pause or hook exception propagates. #1482 <https://github.com/simonw/llm/pull/1482>
  • Chains can now resume from a messages= history ending in unresolved tool calls: the calls are executed through the normal before_call/after_call machinery before the first model call, skipping any that already have results. The execute_tool_calls() method also accepts a new optional tool_calls_list= argument for executing an explicit list of ToolCall objects in place of the calls requested by the response. See Resuming a chain with pending tool calls <#python-api-tools-resume>​. #1482 <https://github.com/simonw/llm/pull/1482>
  • Fixed a bug where the async tool executor silently dropped calls to tools not present in tools= - these now return Error: tool "..." does not exist results, matching the sync executor. #1483 <https://github.com/simonw/llm/pull/1483>

0.32a2 (2026-05-12)

Support for the OpenAI Responses API

Most reasoning-capable OpenAI models now use the /v1/responses <https://developers.openai.com/api/reference/responses/overview> endpoint instead of /v1/chat/completions​. This enables interleaved reasoning across tool calls for GPT-5 class models. #1435 <https://github.com/simonw/llm/pull/1435>

  • New Responses and AsyncResponses model classes driving the OpenAI Responses API. The existing Chat and AsyncChat classes are unchanged so other plugins that import them keep working.
  • The following models now use the Responses API by default: o1, o3-mini, o3, o4-mini, gpt-5, gpt-5-mini, gpt-5-nano, gpt-5.1, gpt-5.2, gpt-5.4, gpt-5.4-mini, gpt-5.4-nano, gpt-5.5 (and their pinned date variants).
  • Use -o chat_completions 1 to fall back to the older /v1/chat/completions code path for any of these models.
  • Encrypted reasoning items are captured as provider_metadata on ReasoningPart objects and round-tripped back to OpenAI on subsequent turns.
  • Reasoning summaries are now requested with "summary": "auto" so visible reasoning text is streamed back where the model produces it, unless --hide-reasoning or hide_reasoning= is set.
  • This means OpenAI prompts run using llm prompt that return reasoning tokens will display those on standard error.

CLI

  • New llm -m model --options flag to list the options supported by a given model. #1441 <https://github.com/simonw/llm/pull/1441>
  • The -R/--no-reasoning option has been renamed to -R/--hide-reasoning​.

Python API

  • New hide_reasoning=True keyword argument on model.prompt(), conversation.prompt(), model.chain(), conversation.chain(), and their async counterparts, exposed to model plugins as prompt.hide_reasoning​. Model plugins can use this to decide <#advanced-model-plugins-reasoning-tokens> if they should request visible reasoning summaries from their providers. #1442 <https://github.com/simonw/llm/pull/1442>
  • New options= dict keyword argument on Model.prompt(), Conversation.prompt(), Response.reply(), and their async equivalents, matching the pattern already used by ​.chain()​. The previous **kwargs form continues to work for backwards compatibility but is no longer documented, and will be removed in the future. #1432 <https://github.com/simonw/llm/pull/1432>

Bug fixes

  • add_tool_call() calls that were not also recorded as stream events are now correctly emitted as ToolCallPart objects when assembling response parts, so they survive serialization via response.to_dict()​. #1433 <https://github.com/simonw/llm/issues/1433>

0.32a1 (2026-04-29)

0.32a0 (2026-04-28)

This alpha introduces a major backwards-compatible refactor. Models can now be prompted with a list of messages, OpenAI Chat Completions style, and the response can now be iterated over as a sequence of mixed types of content, for example reasoning tokens mixed with text tokens mixed with tool calls.

For more background on this release take a look at the annotated release notes <https://simonwillison.net/2026/Apr/29/llm/> on my blog.

Prompt inputs and response outputs are now expressed as a list of Message objects, each containing typed Part objects (text, reasoning, tool calls, tool results, attachments).

The llm CLI tool can now display reasoning tokens while executing a prompt.

Plugin authors should read the expanded Advanced model plugins <#advanced-model-plugins> documentation, which now covers StreamEvent, consuming prompt.messages, and round-tripping opaque provider metadata such as Anthropic extended-thinking signatures and Gemini thoughtSignature values.

Structured messages and streaming events

  • New llm.Message value type and constructor helpers llm.user(), llm.assistant(), llm.system(), and llm.tool_message() for building structured prompt inputs. The helpers accept strings, Attachment instances, or nested Part lists.
  • New messages= keyword argument on model.prompt(), conversation.prompt(), model.chain(), conversation.chain(), and their async counterparts. The prompt=, system=, attachments=, and tool_results= keywords still work and synthesize into the same Message list internally.
  • New response.stream_events() and response.astream_events() methods yielding typed StreamEvent objects (type is one of "text", "reasoning", "tool_call_name", "tool_call_args", "tool_result", plus a redacted=True marker for opaque reasoning). Iterating against response directly continues to yield only text strings.
  • New response.messages() method (async: await response.messages()) returning the assembled list[Message] produced by the model. Calling it forces execution if the response prompt has not yet been executed.
  • New response.reply(prompt=None, **kwargs) method that continues the conversation from any Response, regardless of origin. When the previous response made tool calls and tool_results= was not passed, reply() automatically executes the pending tool calls and threads the results into the next turn. On async responses reply() is awaitable.
  • New response.to_dict() and Response.from_dict(data, *, model=None) for JSON-safe serialization of a full conversation turn — model id, input chain, assembled output (including reasoning parts and provider metadata), options, and audit fields. Reasoning signatures and thoughtSignature values round-trip via provider_metadata, so multi-turn extended thinking works across process boundaries.
  • New llm/serialization.py module exposing MessageDict, PartDict, ResponseDict, PromptDict, UsageDict, AttachmentDict, and the per-Part TypedDicts. Every to_dict() / from_dict() method is annotated with the matching TypedDict.
  • Response.prompt.messages is now the canonical structured input across the entire conversation chain. Conversation.prompt and AsyncConversation.prompt pre-compute the full chain (prior input + prior output + new turn) before constructing the next Prompt, so response.prompt.messages is always exactly what the model was sent.

CLI

  • llm prompt and llm chat now display visible reasoning text to stderr in a dim style while the response streams.
  • New -R/--hide-reasoning flag for llm prompt and llm chat to hide the reasoning stream.
  • llm logs now renders any visible reasoning emitted during a response under a ## Reasoning heading above the response.
  • New reasoning column on the responses table populated from the visible-reasoning text.

0.31 (2026-04-24)

0.30 (2026-03-31)

  • The register_models() plugin hook <#plugin-hooks-register-models> now takes an optional model_aliases parameter listing all of the models, async models and aliases that have been registered so far by other plugins. A plugin with @hookimpl(trylast=True) can use this to take previously registered models into account. #1389 <https://github.com/simonw/llm/issues/1389>
  • Added docstrings to public classes and methods and included those directly in the documentation.

0.29 (2026-03-17)

0.28 (2025-12-12)

0.27.1 (2025-08-11)

0.27 (2025-08-11)

This release adds support for the new GPT-5 family of models from OpenAI. It also enhances tool calling in a number of ways, including allowing templates <#prompt-templates> to bundle pre-configured tools.

New features

Bug fixes and documentation

0.26 (2025-05-27)

Tool support is finally here! This release adds support exposing tools <#tools> to LLMs, previously described in the release notes for 0.26a0 and 0.26a1​.

Read Large Language Models can run tools in your terminal with LLM 0.26 <https://simonwillison.net/2025/May/27/llm-tools/> for a detailed overview of the new features.

Also in this release:

0.26a1 (2025-05-25)

Hopefully the last alpha before a stable release that includes tool support.

Features

Bug fixes

0.26a0 (2025-05-13)

This is the first alpha to introduce support for tools <#tools>! Models with tool capability (which includes the default OpenAI model family) can now be granted access to execute Python functions as part of responding to a prompt.

Tools are supported by the command-line interface <#usage-tools>:

llm --functions '
def multiply(x: int, y: int) -> int:
    """Multiply two numbers."""
    return x * y
' 'what is 34234 * 213345'

And in the Python API <#python-api-tools>, using a new model.chain() method for executing multiple prompts in a sequence:

import llm

def multiply(x: int, y: int) -> int:
    """Multiply two numbers."""
    return x * y

model = llm.get_model("gpt-4.1-mini")
response = model.chain(
    "What is 34234 * 213345?",
    tools=[multiply]
)
print(response.text())

New tools can also be defined using the register_tools() plugin hook <#plugin-hooks-register-tools>​. They can then be called by name from the command-line like this:

llm -T multiply 'What is 34234 * 213345?'

Tool support is currently under active development​. Consult this milestone <https://github.com/simonw/llm/milestone/12> for the latest status.

0.25 (2025-05-04)

0.25a0 (2025-04-10)

0.24.2 (2025-04-08)

0.24.1 (2025-04-08)

0.24 (2025-04-07)

Support for fragments to help assemble prompts for long context models. Improved support for templates to support attachments and fragments. New plugin hooks for providing custom loaders for both templates and fragments. See Long context support in LLM 0.24 using fragments and template plugins <https://simonwillison.net/2025/Apr/7/long-context-llm/> for more on this release.

The new llm-docs <https://github.com/simonw/llm-docs> plugin demonstrates these new features. Install it like this:

llm install llm-docs

Now you can ask questions of the LLM documentation like this:

llm -f docs: 'How do I save a new template?'

The docs: prefix is registered by the plugin. The plugin fetches the LLM documentation for your installed version (from the docs-for-llms <https://github.com/simonw/docs-for-llms> repository) and uses that as a prompt fragment to help answer your question.

Two more new plugins are llm-templates-github <https://github.com/simonw/llm-templates-github> and llm-templates-fabric <https://github.com/simonw/llm-templates-fabric>​.

llm-templates-github lets you share and use templates on GitHub. You can run my Pelican riding a bicycle <https://simonwillison.net/tags/pelican-riding-a-bicycle/> benchmark against a model like this:

llm install llm-templates-github
llm -t gh:simonw/pelican-svg -m o3-mini

This executes this pelican-svg.yaml <https://github.com/simonw/llm-templates/blob/main/pelican-svg.yaml> template stored in my simonw/llm-templates <https://github.com/simonw/llm-templates> repository, using a new repository naming convention.

To share your own templates, create a repository on GitHub under your user account called llm-templates and start saving ​.yaml files to it.

llm-templates-fabric <https://github.com/simonw/llm-templates-fabric> provides a similar mechanism for loading templates from  Daniel Miessler's fabric collection <https://github.com/danielmiessler/fabric>:

llm install llm-templates-fabric
curl https://simonwillison.net/2025/Apr/6/only-miffy/ | \
  llm -t f:extract_main_idea

Major new features:

  • New fragments feature <#fragments>​. Fragments can be used to assemble long prompts from multiple existing pieces - URLs, file paths or previously used fragments. These will be stored de-duplicated in the database avoiding wasting space storing multiple long context pieces. Example usage: llm -f https://llm.datasette.io/robots.txt 'explain this file'​. #617 <https://github.com/simonw/llm/issues/617>
  • The llm logs file now accepts -f fragment references too, and will show just logged prompts that used those fragments.
  • register_template_loaders() plugin hook <#plugin-hooks-register-template-loaders> allowing plugins to register new prefix:value custom template loaders. #809 <https://github.com/simonw/llm/issues/809>
  • register_fragment_loaders() plugin hook <#plugin-hooks-register-fragment-loaders> allowing plugins to register new prefix:value custom fragment loaders. #886 <https://github.com/simonw/llm/issues/886>
  • llm fragments <#fragments-browsing> family of commands for browsing fragments that have been previously logged to the database.
  • The new llm-openai plugin <https://github.com/simonw/llm-openai-plugin> provides support for o1-pro (which is not supported by the OpenAI mechanism used by LLM core). Future OpenAI features will migrate to this plugin instead of LLM core itself.

Improvements to templates:

Other changes:

0.24a1 (2025-04-06)

0.24a0 (2025-02-28)

0.23 (2025-02-28)

Support for schemas, for getting supported models to output JSON that matches a specified JSON schema. See also Structured data extraction from unstructured content using LLM schemas <https://simonwillison.net/2025/Feb/28/llm-schemas/> for background on this feature. #776 <https://github.com/simonw/llm/issues/776>

  • New llm prompt --schema '{JSON schema goes here} option for specifying a schema that should be used for the output from the model. The schemas documentation <#schemas> has more details and a tutorial.
  • Schemas can also be defined using a concise schema specification <#schemas-dsl>, for example llm prompt --schema 'name, bio, age int'​. #790 <https://github.com/simonw/llm/issues/790>
  • Schemas can also be specified by passing a filename and through several other methods <#schemas-specify>​. #780 <https://github.com/simonw/llm/issues/780>
  • New llm schemas family of commands <#help-schemas>: llm schemas list, llm schemas show, and llm schemas dsl for debugging the new concise schema language. #781 <https://github.com/simonw/llm/issues/781>
  • Schemas can now be saved to templates using llm --schema X --save template-name or through modifying the template YAML <#prompt-templates-yaml>​. #778 <https://github.com/simonw/llm/issues/778>
  • The llm logs <#logging> command now has new options for extracting data collected using schemas: --data, --data-key, --data-array, --data-ids​. #782 <https://github.com/simonw/llm/issues/782>
  • New llm logs --id-gt X and --id-gte X options. #801 <https://github.com/simonw/llm/issues/801>
  • New llm models --schemas option for listing models that support schemas. #797 <https://github.com/simonw/llm/issues/797>
  • model.prompt(..., schema={...}) parameter for specifying a schema from Python. This accepts either a dictionary JSON schema definition or a Pydantic BaseModel subclass, see schemas in the Python API docs <#python-api-schemas>​.
  • The default OpenAI plugin now enables schemas across all supported models. Run llm models --schemas for a list of these.
  • The llm-anthropic <https://github.com/simonw/llm-anthropic> and llm-gemini <https://github.com/simonw/llm-gemini> plugins have been upgraded to add schema support for those models. Here's documentation on how to add schema support to a model plugin <#advanced-model-plugins-schemas>​.

Other smaller changes:

0.22 (2025-02-16)

See also LLM 0.22, the annotated release notes <https://simonwillison.net/2025/Feb/17/llm/>​.

  • Plugins that provide models that use API keys can now subclass the new llm.KeyModel and llm.AsyncKeyModel classes. This results in the API key being passed as a new key parameter to their ​.execute() methods, and means that Python users can pass a key as the model.prompt(..., key=) - see Passing an API key <#python-api-models-api-keys>​. Plugin developers should consult the new documentation on writing Models that accept API keys <#advanced-model-plugins-api-keys>​. #744 <https://github.com/simonw/llm/issues/744>
  • New OpenAI model: chatgpt-4o-latest​. This model ID accesses the current model being used to power ChatGPT, which can change without warning. #752 <https://github.com/simonw/llm/issues/752>
  • New llm logs -s/--short flag, which returns a greatly shortened version of the matching log entries in YAML format with a truncated prompt and without including the response. #737 <https://github.com/simonw/llm/issues/737>
  • Both llm models and llm embed-models now take multiple -q search fragments. You can now search for all models matching "gemini" and "exp" using llm models -q gemini -q exp​. #748 <https://github.com/simonw/llm/issues/748>
  • New llm embed-multi --prepend X option for prepending a string to each value before it is embedded - useful for models such as nomic-embed-text-v2-moe <https://huggingface.co/nomic-ai/nomic-embed-text-v2-moe> that require passages to start with a string like "search_document: "​. #745 <https://github.com/simonw/llm/issues/745>
  • The response.json() and response.usage() methods are now documented <#python-api-underlying-json>​.
  • Fixed a bug where conversations that were loaded from the database could not be continued using asyncio prompts. #742 <https://github.com/simonw/llm/issues/742>
  • New plugin for macOS users: llm-mlx <https://github.com/simonw/llm-mlx>, which provides extremely high performance access <https://simonwillison.net/2025/Feb/15/llm-mlx/> to a wide range of local models using Apple's MLX framework.
  • The llm-claude-3 plugin has been renamed to llm-anthropic <https://github.com/simonw/llm-anthropic>​.

0.21 (2025-01-31)

0.20 (2025-01-22)

0.19.1 (2024-12-05)

0.19 (2024-12-01)

0.19a2 (2024-11-20)

0.19a1 (2024-11-19)

0.19a0 (2024-11-19)

  • Tokens used by a response are now logged to new input_tokens and output_tokens integer columns and a token_details JSON string column, for the default OpenAI models and models from other plugins that implement this feature <#advanced-model-plugins-usage>​. #610 <https://github.com/simonw/llm/issues/610>
  • llm prompt now takes a -u/--usage flag to display token usage at the end of the response.
  • llm logs -u/--usage shows token usage information for logged responses.
  • llm prompt ... --async responses are now logged to the database. #641 <https://github.com/simonw/llm/issues/641>

0.18 (2024-11-17)

0.18a1 (2024-11-14)

0.18a0 (2024-11-13)

Alpha support for async models​. #507 <https://github.com/simonw/llm/issues/507>

Multiple smaller changes <https://github.com/simonw/llm/compare/0.17.1...0.18a0>​.

0.17 (2024-10-29)

Support for attachments, allowing multi-modal models to accept images, audio, video and other formats. #578 <https://github.com/simonw/llm/issues/578>

The default OpenAI gpt-4o and gpt-4o-mini models can both now be prompted with JPEG, GIF, PNG and WEBP images.

Attachments in the CLI <#usage-attachments> can be URLs:

llm -m gpt-4o "describe this image" \
  -a https://static.simonwillison.net/static/2024/pelicans.jpg

Or file paths:

llm -m gpt-4o-mini "extract text" -a image1.jpg -a image2.jpg

Or binary data, which may need to use --attachment-type to specify the MIME type:

cat image | llm -m gpt-4o-mini "extract text" --attachment-type - image/jpeg

Attachments are also available in the Python API <#python-api-attachments>:

model = llm.get_model("gpt-4o-mini")
response = model.prompt(
    "Describe these images",
    attachments=[
        llm.Attachment(path="pelican.jpg"),
        llm.Attachment(url="https://static.simonwillison.net/static/2024/pelicans.jpg"),
    ]
)

Plugins that provide alternative models can support attachments, see Attachments for multi-modal models <#advanced-model-plugins-attachments> for details.

The latest llm-claude-3 <https://github.com/simonw/llm-claude-3> plugin now supports attachments for Anthropic's Claude 3 and 3.5 models. The llm-gemini <https://github.com/simonw/llm-gemini> plugin supports attachments for Google's gemini-flash-latest model.

Also in this release: OpenAI models now record their "usage" data in the database even when the response was streamed. These records can be viewed using llm logs --json​. #591 <https://github.com/simonw/llm/issues/591>

0.17a0 (2024-10-28)

Alpha support for attachments​. #578 <https://github.com/simonw/llm/issues/578>

0.16 (2024-09-12)

0.15 (2024-07-18)

0.14 (2024-05-13)

0.13.1 (2024-01-26)

0.13 (2024-01-26)

See also LLM 0.13: The annotated release notes <https://simonwillison.net/2024/Jan/26/llm/>​.

0.12 (2023-11-06)

0.11.2 (2023-11-06)

0.11.1 (2023-10-31)

0.11 (2023-09-18)

LLM now supports the new OpenAI gpt-3.5-turbo-instruct model, and OpenAI completion (as opposed to chat completion) models in general. #284 <https://github.com/simonw/llm/issues/284>

llm -m gpt-3.5-turbo-instruct 'Reasons to tame a wild beaver:'

OpenAI completion models like this support a -o logprobs 3 option, which accepts a number between 1 and 5 and will include the log probabilities (for each produced token, what were the top 3 options considered by the model) in the logged response.

llm -m gpt-3.5-turbo-instruct 'Say hello succinctly' -o logprobs 3

You can then view the logprobs that were recorded in the SQLite logs database like this:

sqlite-utils "$(llm logs path)" \
  'select * from responses order by id desc limit 1' | \
  jq '.[0].response_json' -r | jq

Truncated output looks like this:

  [
    {
      "text": "Hi",
      "top_logprobs": [
        {
          "Hi": -0.13706253,
          "Hello": -2.3714375,
          "Hey": -3.3714373
        }
      ]
    },
    {
      "text": " there",
      "top_logprobs": [
        {
          " there": -0.96057636,
          "!\"": -0.5855763,
          ".\"": -3.2574513
        }
      ]
    }
  ]

Also in this release:

0.10 (2023-09-12)

The two major features in this release are the llm chat command <#usage-chat> and support for embedding binary data​.

See Build an image search engine with llm-clip, chat with models with llm chat <https://simonwillison.net/2023/Sep/12/llm-clip-and-chat/> for more background on these features.

llm chat

The new llm chat command starts an ongoing chat conversation with a model in your terminal. It works with all models supported by LLM and its plugins <#plugins>, including locally installed models such as Llama 2. #231 <https://github.com/simonw/llm/issues/231>

This offers a big performance boost for local models, since they don't need to be freshly loaded into memory for each prompt.

Here's an example chat with Llama 2 13B, provided by the llm-mlc <https://github.com/simonw/llm-mlc> plugin.

llm chat -m mlc-chat-Llama-2-13b-chat-hf-q4f16_1

This starts a chat session:

Type 'exit' or 'quit' to exit
Type '!multi' to enter multiple lines, then '!end' to finish
Type '!edit' to open your default editor and modify the prompt.
> Who are you?
Hello! I'm just an AI, here to assist you with any questions you may have.
My name is LLaMA, and I'm a large language model trained to provide helpful
and informative responses to a wide range of questions and topics. I'm here
to help you find the information you need, while ensuring a safe and
respectful conversation. Please feel free to ask me anything, and I'll do my
best to provide a helpful and accurate response.
> Tell me a joke about otters
Sure, here's a joke about otters:

Why did the otter go to the party?

Because he heard it was a "whale" of a time!

(Get it? Whale, like a big sea mammal, but also a "wild" or "fun" time.
Otters are known for their playful and social nature, so it's a lighthearted
and silly joke.)

I hope that brought a smile to your face! Do you have any other questions or
topics you'd like to discuss?
> exit

Chat sessions are logged to SQLite <#logging> - use llm logs to view them. They can accept system prompts, templates and model options - consult the chat documentation <#usage-chat> for details.

Binary embedding support

LLM's embeddings feature <#embeddings> has been expanded to provide support for embedding binary data, in addition to text. #254 <https://github.com/simonw/llm/pull/254>

This enables models like CLIP <https://openai.com/research/clip>, supported by the new llm-clip <https://github.com/simonw/llm-clip> plugin.

CLIP is a multi-modal embedding model which can embed images and text into the same vector space. This means you can use it to create an embedding index of photos, and then search for the embedding vector for "a happy dog" and get back images that are semantically closest to that string.

To create embeddings for every JPEG in a directory stored in a photos collection, run:

llm install llm-clip
llm embed-multi photos --files photos/ '*.jpg' --binary -m clip

Now you can search for photos of raccoons using:

llm similar photos -c 'raccoon'

This spits out a list of images, ranked by how similar they are to the string "raccoon":

{"id": "IMG_4801.jpeg", "score": 0.28125139257127457, "content": null, "metadata": null}
{"id": "IMG_4656.jpeg", "score": 0.26626441704164294, "content": null, "metadata": null}
{"id": "IMG_2944.jpeg", "score": 0.2647445926996852, "content": null, "metadata": null}
​...

Also in this release

0.10a1 (2023-09-11)

0.10a0 (2023-09-04)

0.9 (2023-09-03)

The big new feature in this release is support for embeddings​. See LLM now provides tools for working with embeddings <https://simonwillison.net/2023/Sep/4/llm-embeddings/> for additional details.

Embedding models <#embeddings> take a piece of text - a word, sentence, paragraph or even a whole article, and convert that into an array of floating point numbers. #185 <https://github.com/simonw/llm/issues/185>

This embedding vector can be thought of as representing a position in many-dimensional-space, where the distance between two vectors represents how semantically similar they are to each other within the content of a language model.

Embeddings can be used to find related documents, and also to implement semantic search - where a user can search for a phrase and get back results that are semantically similar to that phrase even if they do not share any exact keywords.

LLM now provides both CLI and Python APIs for working with embeddings. Embedding models are defined by plugins, so you can install additional models using the plugins mechanism <#installing-plugins>​.

The first two embedding models supported by LLM are:

See Embedding with the CLI <#embeddings-cli> for detailed instructions on working with embeddings using LLM.

The new commands for working with embeddings are:

  • llm embed <#embeddings-cli-embed> - calculate embeddings for content and return them to the console or store them in a SQLite database.
  • llm embed-multi <#embeddings-cli-embed-multi> - run bulk embeddings for multiple strings, using input from a CSV, TSV or JSON file, data from a SQLite database or data found by scanning the filesystem. #215 <https://github.com/simonw/llm/issues/215>
  • llm similar <#embeddings-cli-similar> - run similarity searches against your stored embeddings - starting with a search phrase or finding content related to a previously stored vector. #190 <https://github.com/simonw/llm/issues/190>
  • llm embed-models <#embeddings-cli-embed-models> - list available embedding models.
  • llm embed-db - commands for inspecting and working with the default embeddings SQLite database.

There's also a new llm.Collection <#embeddings-python-collections> class for creating and searching collections of embedding from Python code, and a llm.get_embedding_model() <#embeddings-python-api> interface for embedding strings directly. #191 <https://github.com/simonw/llm/issues/191>

0.8.1 (2023-08-31)

0.8 (2023-08-20)

  • The output format for llm logs has changed. Previously it was JSON - it's now a much more readable Markdown format suitable for pasting into other documents. #160 <https://github.com/simonw/llm/issues/160>

    • The new llm logs --json option can be used to get the old JSON format.
    • Pass llm logs --conversation ID or --cid ID to see the full logs for a specific conversation.
  • You can now combine piped input and a prompt in a single command: cat script.py | llm 'explain this code'​. This works even for models that do not support system prompts <#usage-system-prompts>​. #153 <https://github.com/simonw/llm/issues/153>
  • Additional OpenAI-compatible models <#openai-compatible-models> can now be configured with custom HTTP headers. This enables platforms such as openrouter.ai <https://openrouter.ai/> to be used with LLM, which can provide Claude access even without an Anthropic API key.
  • Keys set in keys.json are now used in preference to environment variables. #158 <https://github.com/simonw/llm/issues/158>
  • The documentation now includes a plugin directory <#plugin-directory> listing all available plugins for LLM. #173 <https://github.com/simonw/llm/issues/173>
  • New related tools <#related-tools> section in the documentation describing ttok, strip-tags and symbex​. #111 <https://github.com/simonw/llm/issues/111>
  • The llm models, llm aliases and llm templates commands now default to running the same command as llm models list and llm aliases list and llm templates list​. #167 <https://github.com/simonw/llm/issues/167>
  • New llm keys (aka llm keys list) command for listing the names of all configured keys. #174 <https://github.com/simonw/llm/issues/174>
  • Two new Python API functions, llm.set_alias(alias, model_id) and llm.remove_alias(alias) can be used to configure aliases from within Python code. #154 <https://github.com/simonw/llm/pull/154>
  • LLM is now compatible with both Pydantic 1 and Pydantic 2. This means you can install llm as a Python dependency in a project that depends on Pydantic 1 without running into dependency conflicts. Thanks, Chris Mungall <https://github.com/cmungall>​. #147 <https://github.com/simonw/llm/pull/147>
  • llm.get_model(model_id) is now documented as raising llm.UnknownModelError if the requested model does not exist. #155 <https://github.com/simonw/llm/issues/155>

0.7.1 (2023-08-19)

0.7 (2023-08-12)

The new Model aliases <#aliases> commands can be used to configure additional aliases for models, for example:

llm aliases set turbo gpt-3.5-turbo-16k

Now you can run the 16,000 token gpt-3.5-turbo-16k model like this:

llm -m turbo 'An epic Greek-style saga about a cheesecake that builds a SQL database from scratch'

Use llm aliases list to see a list of aliases and llm aliases remove turbo to remove one again. #151 <https://github.com/simonw/llm/issues/151>

Notable new plugins

Also in this release

0.6.1 (2023-07-24)

0.6 (2023-07-18)

0.5 (2023-07-12)

LLM now supports additional language models, thanks to a new plugins mechanism <#installing-plugins> for installing additional models.

Plugins are available for 19 models in addition to the default OpenAI ones:

A comprehensive tutorial, writing a plugin to support a new model <#tutorial-model-plugin> describes how to add new models by building plugins in detail.

New features

Smaller improvements

  • llm -s is now a shortcut for llm --system​. #69 <https://github.com/simonw/llm/issues/69>
  • llm -m 4-32k alias for gpt-4-32k​.
  • llm install -e directory command for installing a plugin from a local directory.
  • The LLM_USER_PATH environment variable now controls the location of the directory in which LLM stores its data. This replaces the old LLM_KEYS_PATH and LLM_LOG_PATH and LLM_TEMPLATES_PATH variables. #76 <https://github.com/simonw/llm/issues/76>
  • Documentation covering Utility functions for plugins <#plugin-utilities>​.
  • Documentation site now uses Plausible for analytics. #79 <https://github.com/simonw/llm/issues/79>

0.4.1 (2023-06-17)

0.4 (2023-06-17)

This release includes some backwards-incompatible changes:

  • The -4 option for GPT-4 is now -m 4​.
  • The --code option has been removed.
  • The -s option has been removed as streaming is now the default. Use --no-stream to opt out of streaming.

Prompt templates

Templates <#prompt-templates> is a new feature that allows prompts to be saved as templates and re-used with different variables.

Templates can be created using the llm templates edit command:

llm templates edit summarize

Templates are YAML - the following template defines summarization using a system prompt:

system: Summarize this text

The template can then be executed like this:

cat myfile.txt | llm -t summarize

Templates can include both system prompts, regular prompts and indicate the model they should use. They can reference variables such as $input for content piped to the tool, or other variables that are passed using the new -p/--param option.

This example adds a voice parameter:

system: Summarize this text in the voice of $voice

Then to run it (via strip-tags <https://github.com/simonw/strip-tags> to remove HTML tags from the input):

curl -s 'https://til.simonwillison.net/macos/imovie-slides-and-audio' | \
  strip-tags -m | llm -t summarize -p voice GlaDOS

Example output:

My previous test subject seemed to have learned something new about iMovie. They exported keynote slides as individual images [...] Quite impressive for a human.

The Templates <#prompt-templates> documentation provides more detailed examples.

Continue previous chat

You can now use llm to continue a previous conversation with the OpenAI chat models (gpt-3.5-turbo and gpt-4). This will include your previous prompts and responses in the prompt sent to the API, allowing the model to continue within the same context.

Use the new -c/--continue option to continue from the previous message thread:

llm "Pretend to be a witty gerbil, say hi briefly"

Greetings, dear human! I am a clever gerbil, ready to entertain you with my quick wit and endless energy.

llm "What do you think of snacks?" -c

Oh, how I adore snacks, dear human! Crunchy carrot sticks, sweet apple slices, and chewy yogurt drops are some of my favorite treats. I could nibble on them all day long!

The -c option will continue from the most recent logged message.

To continue a different chat, pass an integer ID to the --chat option. This should be the ID of a previously logged message. You can find these IDs using the llm logs command.

Thanks Amjith Ramanujam <https://github.com/amjith> for contributing to this feature. #6 <https://github.com/simonw/llm/issues/6>

New mechanism for storing API keys

API keys for language models such as those by OpenAI can now be saved using the new llm keys family of commands.

To set the default key to be used for the OpenAI APIs, run this:

llm keys set openai

Then paste in your API key.

Keys can also be passed using the new --key command line option - this can be a full key or the alias of a key that has been previously stored.

See API key management <#api-keys> for more. #13 <https://github.com/simonw/llm/issues/13>

New location for the logs.db database

The logs.db database that stores a history of executed prompts no longer lives at ~/.llm/log.db - it can now be found in a location that better fits the host operating system, which can be seen using:

llm logs path

On macOS this is ~/Library/Application Support/io.datasette.llm/logs.db​.

To open that database using Datasette, run this:

datasette "$(llm logs path)"

You can upgrade your existing installation by copying your database to the new location like this:

cp ~/.llm/log.db "$(llm logs path)"
rm -rf ~/.llm # To tidy up the now obsolete directory

The database schema has changed, and will be updated automatically the first time you run the command.

That schema is included in the documentation <https://llm.datasette.io/en/stable/logging.html#sql-schema>​. #35 <https://github.com/simonw/llm/issues/35>

Other changes

0.3 (2023-05-17)

0.2 (2023-04-01)

  • If a SQLite database exists in ~/.llm/log.db all prompts and responses are logged to that file. The llm init-db command can be used to create this file. #2 <https://github.com/simonw/llm/issues/2>

0.1 (2023-04-01)

Author

Simon Willison

Info

Sep 03, 2026 LLM