Audio Composer — SFX + Music

Two-tier audio system: real AI-generated MP3s when ELEVENLABS_API_KEY is available, deterministic chiptune oscillator synthesis as a zero-cost fallback. The same AudioManager.js handles both transparently — no code change needed in Game.js.

When to use

Run in parallel with the art generation stages (sprite-artist, tile-artist, bg-artist), after GDD is finalized. Also run on an existing game when the user says "add sound", "add music", or "upgrade to ElevenLabs audio."

Two modes

Mode A — ElevenLabs (when ELEVENLABS_API_KEY is set)

Calls POST https://api.elevenlabs.io/v1/sound-generation for each SFX action. Uses the eleven_text_to_sound_v2 model with a genre-flavoured text prompt (e.g. "2D action platformer game, retro 8-bit jump sound, quick upward pitch sweep"). Saves MP3s to public/assets/sfx/<name>.mp3. Adds mp3Path to each entry in sfx.json. AudioManager.js preloads all MP3s as AudioBuffers via decodeAudioData and plays them on demand.

Rate limit: requests are made sequentially with automatic retry on HTTP 429.

Mode B — Web Audio oscillator (no API key, or --no-elevenlabs)

Writes oscillator parameters (freq, dur, type, vol) to sfx.json. AudioManager.js generates sound at runtime using OscillatorNode — no audio files, no network calls, works offline.