Add `description` arg to tool decorators as alternative to docstring

[zhcn000000]

Description

Add a method for passing the ArgSchema of the Agent tool using the Field parameter, instead of necessarily using a docstring

Such As

@agent.tool_plain(name="Add", description="Add two numbers")
def add(
    a: Annotated[int, Field(description="First number")], 
    b: Annotated[int, Field(description="Second Number")],
) -> Annotated[int, Field(description="Result of addition")]:
    return a + b

References

No response

[phemmer]

You partially already can. In your example, the arguments already work. There is no description parameter to tool_plain though, and that still does come from docstring.

model = TestModel(call_tools=[])
agent = Agent(model)

@agent.tool_plain(name="Add")
def add(
    a: Annotated[int, Field(description="First number")],
    b: Annotated[int, Field(description="Second Number")],
) -> Annotated[int, Field(description="Result of addition")]:
    """Add two numbers"""
    return a + b

model_request_orig = model.request
async def model_request(messages, settings, model_request_parameters):
    print(model_request_parameters.function_tools)
    return await model_request_orig(messages, settings, model_request_parameters)
model.request = model_request

async def main():
    await agent.run("...")

asyncio.run(main())

[ToolDefinition(name='Add', parameters_json_schema={'additionalProperties': False, 'properties': {'a': {'description': 'First number', 'type': 'integer'}, 'b': {'description': 'Second Number', 'type': 'integer'}}, 'required': ['a', 'b'], 'type': 'object'}, description='Add two numbers')]

The return value schema is also missing, but ToolDefinition doesn't even have a place for storing the return type. But that's a separate issue: #3122

[DouweM]

@phemmer Thanks for verifying that most of the example already works!

@zhcn000000 You're welcome to submit a PR that adds description to the tool_plain and tool decorators.