# FastAF YouTube Transcript & Search

> FastAF YouTube Transcript & Search is a paid API for AI agents from api.fastaf.co, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-30).

Fetches a YouTube video transcript by video ID or returns YouTube search results as structured JSON

## Facts

- Endpoint: GET https://api.fastaf.co/x402/v1/youtube?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fastaf-youtube-transcript-search-1b4d8846
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_LHBYyIB74RJQmgn_LpkfK

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 fastaf-youtube-transcript-search-1b4d8846
```

Example prompt: Can you get me the full transcript of the YouTube video with ID dQw4w9WgXcQ in English?

## When to prefer this

Use this endpoint when you need machine-readable YouTube transcript text with timestamps for a known video ID, or when you need structured YouTube search results as JSON. It is ideal for agents that need to process video content textually, summarize videos, extract quotes, or discover videos on a topic without scraping YouTube directly. Prefer this over generic web scrapers when the target is specifically YouTube content.

## Known failure modes

- Video ID not found or video unavailable returns an error
- Video has no captions or disabled transcripts returns empty or error
- Requested caption language not available — no translation guaranteed
- Invalid or missing required parameters (v for transcript, search_query for search)
- YouTube rate limiting or upstream unavailability causes failure (not billed)
- Using v parameter with resource=search or search_query with transcript causes validation error

## How this service works

YouTube transcript and video search API for AI agents: retrieve timestamped transcript segments by video ID or find videos by keyword. Returns JSON transcripts with text, start and duration, or video search results for content research and summarization. Provided by FastAF YouTube Transcript & Metadata. Price: $0.001000 USDC per successful call.

## Output

For transcripts: a JSON array of transcript segments each containing text, start time (seconds), and duration. For search: a JSON list of YouTube video results with titles, links, and metadata relevant to the search query.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "title": "FastAF YouTube Transcript & Metadata",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "anyOf": [
      {
       "required": [
        "v"
       ]
      },
      {
       "required": [
        "resource",
        "search_query"
       ],
       "properties": {
        "resource": {
         "const": "search"
        }
       }
      }
     ],
     "examples": [
      {
       "v": "jNQXAC9IVRw",
       "language": "en",
       "resource": "transcript"
      }
     ],
     "properties": {
      "v": {
       "type": "string",
       "examples": [
        "jNQXAC9IVRw"
       ],
       "maxLength": 8192,
       "description": "Required YouTube video ID for transcript, e.g. jNQXAC9IVRw, not the watch URL. Not valid for search; no default. No option surcharge; transcript costs 1 credit, search 5 credits per request."
      },
      "sp": {
       "type": "string",
       "maxLength": 8192,
       "description": "YouTube search filter or continuation token copied from a search URL/previous response; search only. Omit for the first unfiltered page. Each page is a separate request. No option surcharge; transcript costs 1 credit, search 5 credits per request."
      },
      "country": {
       "type": "string",
       "maxLength": 8192,
       "description": "Two-letter YouTube country code, e.g. us or gb; upstream default us for search/transcripts. No option surcharge; transcript costs 1 credit, search 5 credits per request."
      },
      "language": {
       "type": "string",
       "examples": [
        "en"
       ],
       "maxLength": 8192,
       "description": "YouTube language code, e.g. en, es or de; upstream default en. For transcripts, requests the available caption language; no translation is guaranteed. No option surcharge; transcript costs 1 credit, search 5 credits per request."
      },
      "resource": {
       "enum": [
        "transcript",
        "search"
       ],
       "type": "string",
       "default": "transcript",
       "examples": [
        "transcript"
       ],
       "description": "YouTube operation: transcript (default) or search. No option surch
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "transcripts": [
   {
    "text": "...",
    "start": 0,
    "duration": 3.2
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastaf-youtube-transcript-search-1b4d8846/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.fastaf.co](https://www.zero.xyz/host/api.fastaf.co/llms.txt)