Packaging

I always forget how to set up uv properly so that it allows me to do something like

from agents import ...

.
├── src/
│   ├── agents/
│   │   └── __init__.py
│   └── client/
│       └── __init__.py
├── test/
└── pyproject.toml

The answer is modules

[build-system]
requires = ["uv_build>=0.10.0,<0.11.0"]
build-backend = "uv_build"

[tool.uv.build-backend]
module-name = ["agents", "client"]
module-root = "src"

Tools

To expose a python function as a tool you need both a script and build backend.

There’s a lot of guides that tell you to use setuptools or hatch a holdover from pre March 2025 when UV created its own build backend - try it first.

[project.scripts]
agent_example = "src.agents.__init__.py:main"

[build-system]
requires = ["uv_build>=0.10.7,<0.11.0"]
build-backend = "uv_build"

Then you can run it with uvx agent_example