Sound

You design the sound: what plays, where, how loud and from which source. The scripts mix, level and master; the host tools generate. Provider calls (voice, music, effects, transcription) happen only through the host tools, which hold the keys: never call a provider API, and never look for a key, in the sandbox.

Need	Use
A voiceover line	`generate_voiceover(text, voice_id, sandbox_path, ...)`: mp3 plus `<name>.words.json` word timings
An effect, ambience or loop	`generate_sound_effect(prompt, sandbox_path, duration_seconds=..., loop=...)`
A music bed	`generate_music(sandbox_path, prompt=..., length_seconds=...)` or a `composition_plan`; or a track the person supplied
Interface sounds, no key needed	`node /workspace/skills/sound/scripts/synth-cue.mjs <recipe> <out.wav>` (`--list`)
A transcript with word timings	`transcribe_audio(sandbox_path)`
Mix, master, mux, lint	`node /workspace/skills/sound/scripts/score.mjs <jobDir> [plan.json]`
Master one file	`node /workspace/skills/sound/scripts/master.mjs <in> <out> [--target -14] [--true-peak -1]`

Generated files go under <jobDir>/sound-assets/<music|sfx|vo>/<slug>.mp3|wav, where the plan finds them. Every generation spends credits; say what a pass cost.