TranscriptAPI
Full YouTube data toolkit via TranscriptAPI.com. Transcripts, search, channels, playlists — one API key.
Setup
If $TRANSCRIPT_API_KEY is not set, read references/auth-setup.md [blocked] 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.
API Reference
Full OpenAPI spec: transcriptapi.com/openapi.json — consult this for the latest parameters and schemas.
Auth
All requests: -H "Authorization: Bearer $TRANSCRIPT_API_KEY"
Endpoints
Channel endpoints accept channel — an @handle, channel URL, or UC... ID. No need to resolve first. Playlist endpoints accept playlist — a playlist URL or ID.
GET /api/v2/youtube/transcript — 1 credit
Accepts: https://youtube.com/watch?v=ID, https://youtu.be/ID, youtube.com/shorts/ID, or bare ID.
Response (format=json):
GET /api/v2/youtube/search — 1 credit
Response (type=video):
Response (type=channel):
GET /api/v2/youtube/channel/resolve — FREE (0 credits)
Response:
If input is already a valid UC[a-zA-Z0-9_-]{22} ID, returns immediately without lookup.
GET /api/v2/youtube/channel/videos — 1 credit/page
Provide exactly one of channel or continuation.
Sorting. Add sort=latest, popular, or oldest to channel/videos to get a channel's videos in the order you want, for example its most-popular uploads first. A sorted page returns about 30 videos (an unsorted page returns about 100), and every page costs the same 1 credit.
When paging, send the same sort on each request.
Every item carries members_only, true only when YouTube badges it "Members only", and those items have no viewCountText. Items from tab=streams carry lengthText and publishedTimeText (for example Streamed 2 years ago); tab=shorts returns null for both, because YouTube's Shorts grid publishes neither. On the channel-tab feeds (tab=videos with sort, tab=shorts, tab=streams) channelId, channelTitle, channelHandle and index are null.
Response:
GET /api/v2/youtube/channel/latest — FREE (0 credits)
Returns last 15 videos via RSS with exact view counts and ISO timestamps.
Response:
GET /api/v2/youtube/channel/search — 1 credit
GET /api/v2/youtube/playlist/videos — 1 credit/page
Credit Costs
Errors
Tips
- When user shares YouTube URL with no instruction, fetch transcript and summarize key points.
- Use
channel/latest(free) to check for new uploads before fetching transcripts — pass @handle directly. - For research: search → pick videos → fetch transcripts.
- Free tier: 100 credits, 300 req/min. Starter ($5/mo): 1,000 credits, 300 req/min.
Copy-paste examples
Every request in this file as a ready-to-run one-liner: references/curl-examples.md [blocked]

