Video transcript

When to use this

Use it to turn a video into text for summaries, search, research or repurposing. It reads the video's captions: the creator's own or YouTube's auto-generated ones (isGenerated tells them apart).

Pick a language with language (e.g. es); without it you get English when the video has it, else the video's main language. availableLanguages lists every caption track. YouTube's machine translation isn't available, so a language the video has no captions in returns 404.

Videos without captions, and private or removed ones, return 404 not_found.

Parameters

All parameters go in the query string.

Example request

Replace YOUR_API_KEY with your key, or set LURKAPI_KEY for the code. Get a free key.

curl "https://api.lurkapi.com/v1/youtube/video/transcript?url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DdQw4w9WgXcQ" \
  -H "x-api-key: YOUR_API_KEY"

const params = new URLSearchParams({
  url: "https://www.youtube.com/watch?v=dQw4w9WgXcQ",
});
const res = await fetch(`https://api.lurkapi.com/v1/youtube/video/transcript?${params}`, {
  headers: { "x-api-key": process.env.LURKAPI_KEY },
});
const data = await res.json();
if (!data.success) throw new Error(`${data.code}: ${data.error}`);
console.log(data.transcript);

import os
import requests

res = requests.get(
    "https://api.lurkapi.com/v1/youtube/video/transcript",
    params={
        "url": "https://www.youtube.com/watch?v=dQw4w9WgXcQ",
    },
    headers={"x-api-key": os.environ["LURKAPI_KEY"]},
    timeout=60,
)
data = res.json()
if not data["success"]:
    raise RuntimeError(f"{data['code']}: {data['error']}")
print(data["transcript"])

Example response

A real response from this endpoint, captured from the live API and trimmed to a couple of items. Strings over 96 characters (mostly signed media URLs) are cut short and end in ….

{
  "success": true,
  "credits_remaining": 999983,
  "credits_charged": 1,
  "videoId": "dQw4w9WgXcQ",
  "url": "https://www.youtube.com/watch?v=dQw4w9WgXcQ",
  "language": "English",
  "languageCode": "en",
  "isGenerated": false,
  "transcript": [
    {
      "text": "♪ We're no strangers to love ♪",
      "startMs": 18640,
      "endMs": 21880,
      "startTimeText": "0:18"
    },
    {
      "text": "♪ You know the rules and so do I ♪",
      "startMs": 22640,
      "endMs": 26960,
      "startTimeText": "0:22"
    }
  ],
  "transcript_only_text": "♪ We're no strangers to love ♪ ♪ You know the rules and so do I ♪",
  "availableLanguages": [
    {
      "code": "en",
      "name": "English",
      "isGenerated": false
    },
    {
      "code": "en",
      "name": "English",
      "isGenerated": true
    },
    {
      "code": "de-DE",
      "name": "German (Germany)",
      "isGenerated": false
    },
    {
      "code": "ja",
      "name": "Japanese",
      "isGenerated": false
    },
    {
      "code": "pt-BR",
      "name": "Portuguese (Brazil)",
      "isGenerated": false
    },
    {
      "code": "es-419",
      "name": "Spanish (Latin America)",
      "isGenerated": false
    }
  ]
}

Response fields

Every field of a successful response. [] marks a list: a[].b is the b of each item in a. nullable fields can be null; optional fields can be missing.

Caching and freshness

Responses are cached for up to 30 days, so a repeat call within that window can return the same data. It still costs 1 credit.

Errors

Errors return { success: false, error, code, docs } with the HTTP status below. Validation errors, 401/402/429 rejections and 5xx failures are free; not_found is charged (how charging works). All error codes.

Use it in Claude

Once LurkAPI is connected to Claude, this endpoint is the youtube_transcript tool. Ask in plain English, for example:

Use LurkAPI's youtube_transcript with url "https://www.youtube.com/watch?v=dQw4w9WgXcQ" and summarize what you find.

Claude calls youtube_transcript with arguments like these, and each call costs 1 credit:

{
  "url": "https://www.youtube.com/watch?v=dQw4w9WgXcQ"
}

Tool results skip nulls and empty lists to save tokens.