captions

1# Captions
2 
3Extract closed captions from YouTube videos via [TranscriptAPI.com](https://transcriptapi.com).
4 
5## Setup
6 
7If `$TRANSCRIPT_API_KEY` is not set, read [references/auth-setup.md](references/auth-setup.md) and follow the instructions there to get and store the key.
8 
9## Required Headers
10 
11Every request needs two headers:
12 
13- **Authorization:** `Bearer $TRANSCRIPT_API_KEY`
14- **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.
15 
16## GET /api/v2/youtube/transcript
17 
18```bash
19curl -s "https://transcriptapi.com/api/v2/youtube/transcript\
20?video_url=VIDEO_URL&format=json&include_timestamp=true&send_metadata=true" \
21  -H "Authorization: Bearer $TRANSCRIPT_API_KEY" \
22  -H "User-Agent: YourAgent/1.0"
23```
24 
25| Param               | Required | Default | Values                              |
26| ------------------- | -------- | ------- | ----------------------------------- |
27| `video_url`         | yes      | —       | YouTube URL or video ID             |
28| `format`            | no       | `json`  | `json` (structured), `text` (plain) |
29| `include_timestamp` | no       | `true`  | `true`, `false`                     |
30| `send_metadata`     | no       | `false` | `true`, `false`                     |
31 
32**Response** (`format=json` — best for accessibility/timing):
33 
34```json
35{
36…