Paint Arena Coworld Example

Paint Arena Coworld Example

Paint Arena is the smallest complete Coworld example in this package. It has one game image and one bundled player entrypoint. The same image also carries reference grader, diagnoser, and optimizer role entrypoints so the manifest shows the full Coworld role shape without extra build contexts. Reporters are not containers — a manifest declares reporter references to wasm components or platform reporter versions; see the Reporter role for the v2 contract.

The game is two-player and tick-based. Each player moves around a grid and paints the tile they are standing on. Painting overwrites the previous owner. Final scores are the number of tiles painted with each player's color.

Build And Upload

From the repository root, build from the packaged example files:

uv run coworld build --project packages/coworld/src/coworld/examples/paintarena --version 0.1.0
uv run coworld upload-coworld packages/coworld/src/coworld/examples/paintarena/dist/coworld_manifest.json

Play Locally

From the repository root:

uv run coworld play packages/coworld/src/coworld/examples/paintarena/dist/coworld_manifest.json

The command prints:

• one player client link per slot,
• a global viewer link,
• an admin link for pause, resume, and tick-rate controls,
• the local artifact directory for results, replay, and logs.

Open both player links before playing. The episode starts after both player websocket clients connect.

Run A Local Episode

To run the full game with the bundled sweep-painter player image:

uv run coworld run-episode packages/coworld/src/coworld/examples/paintarena/dist/coworld_manifest.json

This is the same local smoke-test shape a league player would use with their own image.

Reference Optimizer

The manifest declares paint-arena-reference-optimizer, a minimal optimizer role that writes a deterministic JSON plan from the Coworld manifest and optional prior report, grader, and diagnoser artifact URI lists.

Reference Grader And Diagnoser

The manifest declares paint-arena-grader and paint-arena-diagnoser as deterministic one-shot supporting runnables. Both consume an episode bundle. The grader writes a JSON score equal to absolute painted-tile margin divided by board area. The diagnoser also receives COGAME_TARGET_POLICY_URI and writes a zip containing Markdown advice plus structured findings.

Certify

From the repository root:

uv run coworld certify packages/coworld/src/coworld/examples/paintarena/dist/coworld_manifest.json

Certification runs the game and bundled sweep-painter policy containers end to end, then validates the results and replay artifacts.

View A Replay

After play or certify writes a replay artifact, start a replay viewer from the repository root:

uv run coworld replay tmp/paintarena/coworld_manifest.json path/to/replay

The command prints a replay client link and waits for the replay container to exit.

Default Episode

The default variant is configured in coworld_manifest_template.json:

• width: 12
• height: 8
• max_ticks: 100
• tick_rate: 5

That makes the episode last about 20 seconds.