{
  "source": {
    "type": "url",
    "url": "s3://bucket/video.mp4"
  },
  "description": {
    "style": "neutral",
    "language": "en",
    "density": "standard"
  },
  "voice": {
    "provider": "elevenlabs",
    "voiceId": "rachel",
    "speed": 1.0
  },
  "output": {
    "formats": ["mp3", "webvtt", "json"],
    "destination": "s3://output-bucket/"
  },
  "callback": {
    "url": "https://your-app.com/webhook"
  }
}