youtube-fetch

Overview

This skill retrieves YouTube video content (metadata and transcripts) using yt-dlp. WebFetch does not work reliably for YouTube (dynamic content, SSL issues). yt-dlp is the reliable alternative.

Prerequisite: yt-dlp must be installed (pip install yt-dlp).

Workflow

1. Ensure yt-dlp is available (install if needed):

   which yt-dlp || pip install yt-dlp
   

2. Fetch metadata for each video:

   yt-dlp --skip-download --print '%(title)s|||%(uploader)s|||%(description)s' 'VIDEO_URL'
   

3. Fetch the auto-generated transcript:

   mkdir -p /tmp/yt-transcripts
   yt-dlp --write-auto-sub --skip-download --sub-lang en -o '/tmp/yt-transcripts/%(id)s' 'VIDEO_URL'
   

   The transcript lands at /tmp/yt-transcripts/VIDEO_ID.en.vtt.

4. Clean the VTT file into plain text (strip timestamps and tags):

   sed '/^WEBVTT/d;/^Kind:/d;/^Language:/d;/^[0-9][0-9]:[0-9][0-9]/d;/^$/d;s/<[^>]*>//g' /tmp/yt-transcripts/VIDEO_ID.en.vtt | awk '!seen[$0]++'
   

5. If the transcript is too large to read at once, pipe through head -N / tail -n +N to read in chunks.

6. If no English auto-subs are available, try without --sub-lang:

   yt-dlp --write-auto-sub --skip-download -o '/tmp/yt-transcripts/%(id)s' 'VIDEO_URL'
   

   Then check ls /tmp/yt-transcripts/VIDEO_ID.*.vtt for available languages.

7. If SSL errors occur, add --no-check-certificate.

Output Format

Present results per video as:

### Video: [Title]
**Channel:** [Uploader]
**URL:** [Original URL]

**Description:**
[Video description text]

**Transcript:**
[Cleaned transcript text, or summary if too long for context]

Parallel Processing

When multiple YouTube URLs are provided, run all metadata fetches in parallel (separate Bash calls in one message), then all transcript downloads in parallel. Process sequentially only if outputs depend on each other.

Examples

Single Video

Input: "What does this video talk about? https://youtu.be/abc123"

Action: Run steps 1-4, return metadata + cleaned transcript.

Batch

Input: User provides 4 YouTube URLs for research compilation.

Action: Fetch all 4 metadata calls in parallel, then all 4 transcript downloads in parallel, then clean and return.

No Captions Available

Input: A video with no auto-generated subtitles.

Action: Report "No English auto-subs available for [title]" and list any other language VTT files found. Return metadata and description only.