yuutools

Explicit, async-first tool framework for LLM agents.

Install

uv add yuutools

Usage

import yuutools as yt

def get_z(ctx) -> int:
    return ctx.multiplier

@yt.tool(
    params={"x": "first operand", "y": "list of ints to sum"},
    name="goodtool",
    description="Add x + sum(y) + z",
)
async def goodtool(x: int, y: list[int], z: int = yt.depends(get_z)):
    return x + sum(y) + z

# Registry
manager = yt.ToolManager([goodtool])

tool = manager["goodtool"]
print(tool.spec.to("json_schema"))

# Bind context and run
result = await tool.bind(ctx).run(x=1, y=[2, 3])

@yt.tool

Decorator that turns a function into a Tool. Parameters:

• params — {name: description} mapping for the LLM schema
• name — override tool name (default: __name__)
• description — tool description (default: first docstring line)

yt.depends(resolver)

Marks a parameter as context-injected. The resolver is called with the bound context at execution time. Hidden from the generated spec.

ToolSpec.to(fmt)

Serialize to "json_schema" or "yaml" (requires yuutools[yaml]).

ToolManager

Name-keyed registry with [] lookup, iteration, and .specs() for bulk JSON schema export.

License

MIT