| name | develop-web-game |
| description | Use when Codex is building or iterating on a web game (HTML/JS) and needs a reliable development + testing loop: implement small changes, run a Playwright-based test script with short input bursts and intentional pauses, inspect screenshots/text, and review console errors with render_game_to_text. |
Develop Web Game
Build games in small verified steps: implement, run short input bursts, inspect
text state plus screenshots, fix, repeat.
Load Detail On Demand
references/setup.md: environment variables and Playwright prerequisites.references/test-loop.md: action bursts, screenshots, console checks.references/game-guidelines.md: canvas, visuals, text state, deterministic
time, fullscreen.references/progress-tracking.md: progress.md handling across agents.references/action_payloads.json: valid action keys and payload shape.
Setup
export CODEX_HOME="${CODEX_HOME:-$HOME/.codex}"
export WEB_GAME_CLIENT="$CODEX_HOME/skills/develop-web-game/scripts/web_game_playwright_client.js"
export WEB_GAME_ACTIONS="$CODEX_HOME/skills/develop-web-game/references/action_payloads.json"
Required Game Hooks
- Single primary canvas.
window.render_game_to_text() returning concise JSON game state.- Prefer deterministic
window.advanceTime(ms) for stable automated checks.
Iteration Loop
- Define one feature/behavior goal.
- Make smallest coherent code change.
- Run
$WEB_GAME_CLIENT with short input bursts after each meaningful change.
- Inspect latest text output, screenshot, and console errors.
- Verify all affected controls and state transitions end-to-end.
- Fix first concrete failure, then rerun.
- Reset between unrelated scenarios.
Read only focused references needed for current game task.
Example:
node "$WEB_GAME_CLIENT" --url http://localhost:5173 --actions-file "$WEB_GAME_ACTIONS" --iterations 3 --pause-ms 250
Signoff Bar
- New behavior works through actual controls, not only state injection.
render_game_to_text matches visible game state.- Screenshots show gameplay beyond start/menu when gameplay changed.
- Important interactions cover cause, intermediate state, and outcome.
- Console has no new unhandled errors.
- Visual state is readable: key objects visible, text minimal, no broken layout.
