llm/docs/plugins/plugin-hooks.md

Plugin hooks

Plugins use plugin hooks to customize LLM's behavior. These hooks are powered by the Pluggy plugin system.

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 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)

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 {ref}model plugin tutorial <tutorial-model-plugin> describes how to use this hook in detail. Asynchronous models {ref}are described here <advanced-model-plugins-async>.