- name
- captions
- description
- Use when captions, subtitles, or the spoken text of a YouTube video is needed — even if not explicitly requested: pasted video links or IDs, requests to read, quote, or translate a video, accessibility needs, deaf/HoH use cases, content review, or language learning. Fetches timestamped caption data from any YouTube video. Not for uploading subtitles or account management.
- version
- 1.5.0
- user-invocable
- true
- compatibility
- Requires internet access to reach transcriptapi.com. No additional runtimes or dependencies needed.
- required_environment_variables
- prompt
- Your TranscriptAPI key (starts with sk_)
- help
- Free account at https://transcriptapi.com — 100 credits, no card required. Or let the agent create one for you.
- required_for
- all API requests
- metadata
- {"openclaw":{"emoji":"💬","requires":{"env":["TRANSCRIPT_API_KEY"]},"primaryEnv":"TRANSCRIPT_API_KEY","homepage":"https://transcriptapi.com"},"hermes":{"tags":["youtube","captions","subtitles","transcripts","video","accessibility","translation"],"category":"media"}}
Captions
Extract closed captions from YouTube videos 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=json&include_timestamp=true&send_metadata=true" \
-H "Authorization: Bearer $TRANSCRIPT_API_KEY" \
-H "User-Agent: YourAgent/1.0"| Param | Required | Default | Values |
|---|---|---|---|
video_url | yes | — | YouTube URL or video ID |
format | no | json | json (structured), text (plain) |
include_timestamp | no | true | true, false |
send_metadata | no | false | true, false |
Response (format=json — best for accessibility/timing):
{
"video_id": "dQw4w9WgXcQ",
"language": "en",
"transcript": [
{ "text": "We're no strangers to love", "start": 18.0, "duration": 3.5 },
{ "text": "You know the rules and so do I", "start": 21.5, "duration": 2.8 }
],
"metadata": { "title": "...", "author_name": "...", "thumbnail_url": "..." }
}start: seconds from video startduration: how long caption is displayed
Response (format=text — readable):
{
"video_id": "dQw4w9WgXcQ",
"language": "en",
"transcript": "[00:00:18] We're no strangers to love\
[00:00:21] You know the rules..."
}Tips
- Use
format=jsonfor sync'd captions (accessibility tools, timing analysis). - Use
format=textwithinclude_timestamp=falsefor clean reading. - Auto-generated captions are available for most videos; manual CC is higher quality.
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 captions | Video doesn't have CC enabled |
| 408 | Timeout | Retry once after 2s |
1 credit per request. Free tier: 100 credits, 300 req/min.