tool.py

from typing import Callable
import json


class Tool:
    def __init__(self, name: str, fn: Callable, signature: str):
        self.name = name
        self.fn = fn
        self.signature = signature

    def __str__(self):
        return self.signature

    def __call__(self, **kwargs):
        return self.fn(**kwargs)


def tool(func: Callable):
    def wrapper():
        metadata = extract_metadata(func)
        return Tool(metadata["name"], func, json.dumps(metadata))

    return wrapper()


def extract_metadata(fn: Callable) -> dict:
    dic = {
        "name": fn.__name__,
        "description": fn.__doc__,
        "parameters": {}
    }

    for k, v in fn.__annotations__.items():
        if k != "return":
            dic["parameters"][k] = v.__name__

    return dic