develop-web-game

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

1. Define one feature/behavior goal.
2. Make smallest coherent code change.
3. Run $WEB_GAME_CLIENT with short input bursts after each meaningful change.
4. Inspect latest text output, screenshot, and console errors.
5. Verify all affected controls and state transitions end-to-end.
6. Fix first concrete failure, then rerun.
7. 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.