Subtitles

Subtitles

Fetch YouTube video subtitles via TranscriptAPI.com.

Setup

If $TRANSCRIPT_API_KEY is not set, read references/auth-setup.md and follow the instructions there to get and store the key.

Required Headers

Every request needs two headers:

• Authorization: Bearer $TRANSCRIPT_API_KEY
• User-Agent: your agent's name and version if known (e.g. HermesAgent/0.11.0, ClaudeCode/1.0). Version is optional — agent name alone is fine. Do not omit this header or send a bare default — Cloudflare will return a 403 (error code 1010) and block the request.

GET /api/v2/youtube/transcript

curl -s "https://transcriptapi.com/api/v2/youtube/transcript\
?video_url=VIDEO_URL&format=text&include_timestamp=false&send_metadata=true" \
  -H "Authorization: Bearer $TRANSCRIPT_API_KEY" \
  -H "User-Agent: YourAgent/1.0"

| Param | Values | Use case |

| ------------------- | ----------------------- | ---------------------------------------------- |

| video_url | YouTube URL or video ID | Required |

| format | json, text | json for sync'd subs with timing |

| include_timestamp | true, false | false for clean text for reading/translation |

| send_metadata | true, false | Include title, channel, description |

For language learning — clean text without timestamps:

curl -s "https://transcriptapi.com/api/v2/youtube/transcript\
?video_url=VIDEO_ID&format=text&include_timestamp=false" \
  -H "Authorization: Bearer $TRANSCRIPT_API_KEY" \
  -H "User-Agent: YourAgent/1.0"

For translation — structured segments:

curl -s "https://transcriptapi.com/api/v2/youtube/transcript\
?video_url=VIDEO_ID&format=json&include_timestamp=true" \
  -H "Authorization: Bearer $TRANSCRIPT_API_KEY" \
  -H "User-Agent: YourAgent/1.0"

Response (format=json):

{
  "video_id": "dQw4w9WgXcQ",
  "language": "en",
  "transcript": [
    { "text": "We're no strangers to love", "start": 18.0, "duration": 3.5 }
  ]
}

Response (format=text, include_timestamp=false):

{
  "video_id": "dQw4w9WgXcQ",
  "language": "en",
  "transcript": "We're no strangers to love\nYou know the rules and so do I..."
}

Tips

• Many videos have auto-generated subtitles in multiple languages.
• Use format=json to get timing for each line (great for sync'd reading).
• Use include_timestamp=false for clean text suitable for translation apps.

Errors

| Code | Meaning | Action |

| -------- | ---------------- | ---------------------------------------------- |

| 401 | Bad API key | Check key |

| 402 | No credits | transcriptapi.com/billing |

| 403/1010 | Cloudflare block | Add or fix User-Agent header |

| 404 | No subtitles | No subtitles available |

| 408 | Timeout | Retry once after 2s |

1 credit per request. Free tier: 100 credits, 300 req/min.