stable-audio

name	stable-audio
description	Generate SFX and music using the local Stable Audio 3 server. Trigger on requests to generate audio, create sound effects, make music, or anything involving Stable Audio, SFX, or sound generation.

Stable Audio 3 — Local Audio Generation

Generate audio files (SFX and music) via the local Stable Audio 3 Next.js API.

Prerequisites

The dev server must be running on http://localhost:3007. The skill will auto-start it if needed.

1. Ensure the server is running

curl -sf http://localhost:3007 > /dev/null 2>&1 && echo "OK" || echo "DOWN"

If DOWN, start it from the project root:

cd /Users/probello/Repos/stable-audio-3-lab && make dev

Run the above with run_in_background, then wait for it to be ready:

until curl -sf http://localhost:3007 > /dev/null 2>&1; do sleep 2; done && echo "READY"

If the server doesn't respond within 30 seconds, stop and tell the user.

2. Generate audio

POST http://localhost:3007/api/generate with JSON body.

Parameters

Param	Type	Required	Default	Description
prompt	string	yes	—	Description of desired audio (8–1000 chars)
mode	"sfx" or "music"	yes	—	Generation mode. Determines defaults below.
model	string	no	"medium" (music) / "small-sfx" (sfx)	"small-sfx", "small-music", or "medium"
duration	number	yes	60 (music)	Length in seconds. For SFX, choose an appropriate duration for the sound (1–10s for UI stings/impacts, 10–30s for ambience/atmospheres). Small models max 120s, medium max 380s.
steps	integer	no	10	Diffusion steps (4–50). Default 10. Use 20 if the user asks for high quality.
cfgScale	number	no	2	Prompt strength (0–12). Default 2.
format	"mp3" or "wav"	no	"mp3"	Output format
seed	integer	no	random	Reproducibility seed (0–2147483647). Same seed + same settings = same output.
negativePrompt	string	no	""	What to avoid (max 500 chars)
mock	boolean	no	false	Fast fake audio for testing without model inference
title	string	no	—	Explicit title for the track. Slugified into the filename (e.g. "Neon Pulse" → neon_pulse). In SFX mode the slug gets an _sfx suffix (e.g. door_slam_sfx.mp3). Collisions append , so nothing is overwritten.

Title resolution: If title is provided, it is used directly (slugified; _sfx suffix in SFX mode). Otherwise, if autoTitle is true, the server calls Ollama to generate a title from the prompt. If neither is set, the filename falls back to sa3-{mode}-{timestamp}.{format}. Requires Ollama running locally (OLLAMA_HOST/OLLAMA_PORT, default 127.0.0.1:11434); model set by OLLAMA_TITLE_MODEL.

Model guide

Model	Best for	Max duration
small-sfx	Sound effects, Foley, UI stings	120s
small-music	Fast local full-song sketches	120s
medium	Higher musicality, long-form up to ~6:20	380s

Example: SFX with auto-title

curl -s -X POST http://localhost:3007/api/generate \
  -H 'Content-Type: application/json' \
  -d '{
    "prompt": "cinematic spaceship door opening, hydraulic hiss, low metallic rumble, clean tail",
    "mode": "sfx",
    "model": "small-sfx",
    "duration": 6,
    "steps": 10,
    "cfgScale": 2,
    "format": "mp3",
    "autoTitle": true
  }'

Example: Music with explicit title

curl -s -X POST http://localhost:3007/api/generate \
  -H 'Content-Type: application/json' \
  -d '{
    "prompt": "lofi hip hop loop, dusty drums, mellow rhodes chords, vinyl texture, 82 BPM",
    "mode": "music",
    "model": "medium",
    "duration": 60,
    "steps": 10,
    "cfgScale": 2,
    "format": "mp3",
    "title": "Dusty Afternoon"
  }'

Defaults by mode

• Music: use "model": "medium", "duration": 60 unless the user specifies otherwise.
• SFX: use "model": "small-sfx". The agent MUST choose a duration appropriate for the requested sound — short for transient effects (2–6s), longer for evolving/atmospheric sounds (10–30s). Never default to 60s for SFX.

3. Handle the response

Success:

{
  "ok": true,
  "audioUrl": "/outputs/dusty_afternoon.mp3",
  "metadataUrl": "/outputs/dusty_afternoon.json",
  "filename": "dusty_afternoon.mp3",
  "title": "Dusty Afternoon",
  "meta": { ... }
}

Report to the user:

• The title (if generated): Dusty Afternoon
• The filename: dusty_afternoon.mp3
• The local file path: /Users/probello/Repos/stable-audio-3-lab/public/outputs/dusty_afternoon.mp3
• The browser URL: http://localhost:3007/outputs/dusty_afternoon.mp3

Failure:

{ "ok": false, "error": "Python generator failed", "detail": { ... } }

Surface the error field to the user. If the error mentions Python or model loading, the user may need to check their Stable Audio 3 setup (MLX weights, Python environment).