Command Notes: What uv run Does

The common command is:

uv run python examples/21_react_loop.py

It means: run this Python file inside the environment managed by uv.

Recommended Version

Start with:

uv run python examples/21_react_loop.py

If it works, you do not need the longer version.

Longer Version

You may also see:

PYTHONPATH=src uv run --no-sync python examples/21_react_loop.py

Part	Meaning	When useful
PYTHONPATH=src	Tells Python where the local package lives.	If imports fail.
uv run	Runs a command in the project environment.	Almost always.
--no-sync	Runs without syncing dependencies first.	When the env is already ready.
python examples/...	The actual Python script.	This is the main part.

You may also see:

UV_CACHE_DIR=.uv_cache uv run ...

That only moves the uv cache into the repo folder. It is useful in sandboxes or CI, but not required for normal reading.