CartPole walkthrough

The Quickstart has the shortest copy-and-paste version. This page runs the example files from the RLMesh repository. Clone it and run these commands from its root; they do not run from an installed Python package alone.

Serve CartPole

From the repository root, start the server in one terminal:

uv run python examples/python/quickstart/serve_gymnasium.py

serve_gymnasium.py makes the Gymnasium environment and hands it to EnvServer, which inspects the spaces, binds the endpoint, and keeps Gymnasium inside the server process. The client never imports it. See Serving Environments for the server API.

Connect a client

In a second terminal:

uv run python examples/python/quickstart/eval.py

eval.py connects a RemoteEnv and drives the Gymnasium loop with sampled actions. RemoteEnv learns observation_space and action_space from the server on connect, so the sampled-action loop runs without any environment-specific imports. Remote Clients covers the client side.

Swap environments

serve_gymnasium.py takes any Gymnasium registration through --env-id:

uv run python examples/python/quickstart/serve_gymnasium.py --env-id Acrobot-v1

To run several servers side by side, give each its own --address:

uv run python examples/python/quickstart/serve_gymnasium.py --address 127.0.0.1:5556

eval.py only needs the matching --address; nothing else about the loop changes.

For a server with no Gymnasium dependency, serve.py serves a tiny Gymnasium-shaped CounterEnv defined in the same directory:

uv run python examples/python/quickstart/serve.py