# glim.sh YouTube Transcript Fetcher

> glim.sh YouTube Transcript Fetcher is a paid API for AI agents from surf.cascade.fyi, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Fetches the subtitle/caption transcript (VTT format) for a YouTube video by video ID, optionally filtered by caption origin and language

## Facts

- Endpoint: POST https://surf.cascade.fyi/api/v1/youtube/get
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/glim-sh-youtube-transcript-fetcher-1c4519fb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ub3HASDjAaWgrJDAemawH

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability glim-sh-youtube-transcript-fetcher-1c4519fb -d '<json body>'
```

Example prompt: Can you grab the uploader-provided English transcript for the YouTube video with ID dQw4w9WgXcQ so I can read what was said?

## When to prefer this

Use this endpoint when you need the transcript or captions of a YouTube video without managing YouTube Data API keys or a scraping stack. Ideal for agents that need to read, summarize, or analyze video content. Prefer this over YouTube's official API when you want pay-per-call pricing with no OAuth setup, or when you need a simple presigned download URL for the VTT file.

## Known failure modes

- Invalid or non-existent video ID returns an error — IDs must be exactly 11 characters
- Video has no captions in the requested language — returns empty or error response
- Unsupported language_code value causes no matching transcript to be found
- Presigned download_url expires after the expires_at timestamp — must be used promptly
- Payment failure (x402 protocol) if USDC balance is insufficient — call is not executed

## How this service works

Fetch a YouTube transcript from a video URL or 11-char id (video_id, also accepted as ref or url); returns a presigned download URL to the transcript

## Output

A JSON object containing a presigned download URL to a VTT-format caption file, the video ID, language code, caption origin (uploader_provided or auto_generated), file size in bytes, character count, content type, and an expiry timestamp for the download URL.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "format": {
   "enum": [
    "inline",
    "url"
   ],
   "type": "string",
   "default": "inline",
   "description": "'inline' (default): include the transcript in the response when it fits the inline cap; otherwise omit it and set transcript_omitted_reason. 'url': never include the transcript; caller fetches download_url. download_url is always present."
  },
  "origin": {
   "enum": [
    "uploader_provided",
    "auto_generated"
   ],
   "type": "string",
   "default": "uploader_provided",
   "description": "'uploader_provided' for human captions (default), 'auto_generated' for YouTube auto-captions."
  },
  "video_id": {
   "type": "string",
   "minLength": 1,
   "description": "YouTube video URL or 11-char video id (e.g. https://youtu.be/dQw4w9WgXcQ, https://www.youtube.com/watch?v=dQw4w9WgXcQ, or dQw4w9WgXcQ). Also accepted as `ref` or `url`."
  },
  "language_code": {
   "type": "string",
   "default": "en",
   "maxLength": 10,
   "minLength": 2,
   "description": "ISO 639-1 language code (e.g. 'en', 'de', 'fr')"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "origin": "uploader_provided",
  "video_id": "dQw4w9WgXcQ",
  "expires_at": "2026-04-21T13:00:00Z",
  "size_bytes": 4096,
  "content_type": "text/vtt",
  "download_url": "https://...presigned...",
  "length_chars": 3500,
  "language_code": "en"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/glim-sh-youtube-transcript-fetcher-1c4519fb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from surf.cascade.fyi](https://www.zero.xyz/host/surf.cascade.fyi/llms.txt)