music-gen

name	music_gen
description	Generate a music clip from a text prompt via OpenRouter's Google Lyria model and play it directly inside the widget. Files are persisted to the skill's private state directory and streamed through an extension route for both inline playback and download.
version	0.5.3
type	extension
runtime	python3
entry	plugin.py
permissions	["net","tool","route","widget","read_settings"]
env_from_settings	["OPENROUTER_API_KEY"]
when_to_use	User wants to generate music or an audio clip from a text prompt and listen to it inline in the web UI.
ui_tab	{"tab_id":"music_gen","title":"Music generator","icon":"music","render":{"kind":"declarative","schema_version":1,"components":[{"type":"form","title":"Generate a music clip","target":"result","route":"generate","method":"POST","job":true,"status_route":"status","interval_ms":2000,"max_ticks":180,"submit_label":"Generate","fields":[{"name":"prompt","label":"Prompt","type":"textarea","required":true}]},{"type":"status","target":"result","idle":"Enter a music prompt and press Generate. Typical latency: 30–60 seconds.","loading":"Generating music — this usually takes 30–60 seconds…","success":"Done.","error":"Generation failed."},{"type":"markdown","target":"result","path":"error"},{"type":"audio","target":"result","path":"clip_url","label":"Generated audio"},{"type":"file","target":"result","path":"clip_url","label":"Download audio"},{"type":"kv","target":"result","fields":[{"path":"detected","label":"Format"},{"path":"mime","label":"MIME"},{"path":"file_size_bytes","label":"File size"}]}]}}

Music generation widget

An extension skill that renders a music generator inside the Widgets tab. Type a prompt, press Generate, and the resulting clip plays directly in the card with a Download audio button.

Backed by OpenRouter's SSE audio API and Google's google/lyria-3-pro-preview model. Lyria produces 48 kHz stereo audio; each request is capped at 20 MB and a 180-second deadline.

Persistence and download

Every generation writes the clip to the skill state directory: ~/Ouroboros/data/state/skills/music_gen/audio_<12 hex>.<ext>.

Both the <audio> player and the Download audio button stream this file via GET /api/extensions/music_gen/download?clip_id=.... No data URLs in DOM.

The download route does NOT need the OPENROUTER_API_KEY grant — already persisted clips are accessible even if the grant is later revoked.

Setup

1. Put your OpenRouter API key into Ouroboros Settings → Providers → OpenRouter.
2. Run review_skill(skill="music_gen") and wait for a PASS verdict.
3. Skills tab → Grant access for OPENROUTER_API_KEY.
4. Enable the skill. 5. Widgets tab → Music generator card.

Usage

• Via the widget: type a prompt, press Generate, wait 30–60 s. Player
  • Download button appear; a small kv panel shows format/MIME/size.
• Via the agent: call ext_<token>_music_gen_generate(prompt="..."). Returns JSON with file_path, clip_id, clip_url, bytes, mime, detected, model, prompt_used.

Security model

Same as image_gen: key via PluginAPI.get_settings only; single-host allowlist; two-layer path traversal defense on download route.

Limits

• One clip per request. Lyria ≈ $0.08/song on OpenRouter (Mar 2026).
• Max 20 MB decoded audio. Timeout: 180 s.
• State dir not auto-cleaned — delete old files freely.