docs/engine_control.md

Engine Control API

Endpoint

POST /api/engine/control

Payload

{
  "narration_enabled": true,
  "bg_enabled": true
}

• narration_enabled – When false, /api/tts/preview returns an empty URL, skipping TTS generation.
• bg_enabled – When true, generated narration is mixed with a background‑music file (first file found in Assets/background_music).

Persistence

The flags are stored in engine_control_flags.json at the project root, allowing the state to survive server restarts.

UI Integration

• The Narration and Music checkboxes call this endpoint on change.
• The dashboard reads the flags on load to initialise the UI state.