summarize-youtube

name	summarize-youtube
description	This skill should be used when the user asks to "summarize a YouTube video", "summarize this video", pastes a YouTube URL and asks for a summary, says "what is this video about", or asks to "extract a transcript" from a YouTube link.
allowed-tools	Bash

Summarize YouTube Videos

Overview

Extract transcripts from YouTube videos using the summarize CLI (@steipete/summarize) and produce a concise summary. The transcript is extracted locally and then summarized in-context by Claude.

When To Use

Use this skill when:

• The user provides a YouTube URL and wants a summary.
• The user asks to extract or read a YouTube transcript.
• The user pastes a YouTube link and asks "what is this about?"

Workflow

1. Receive a YouTube URL from the user.
2. Run summarize "<URL>" --extract --youtube auto --timestamps to extract the raw transcript.
3. If --timestamps output is too long (over ~30k chars), re-run without --timestamps or truncate.
4. Read the extracted transcript and produce a structured summary including:
   • Title (from the transcript metadata if available)
   • Key topics covered
   • Summary (3-5 paragraphs depending on video length)
   • Notable quotes or takeaways (if applicable)

CLI Reference

# Extract raw transcript (preferred - lets Claude summarize)
summarize "<URL>" --extract --youtube auto --timestamps

# Extract and format as markdown via LLM (alternative)
summarize "<URL>" --extract --format md --markdown-mode llm

# Extract with slide screenshots (requires ffmpeg + yt-dlp)
summarize "<URL>" --slides --extract

YouTube transcript modes

Mode	Behavior
auto (default)	youtubei -> captionTracks -> yt-dlp -> Apify
web	youtubei -> captionTracks only
no-auto	Creator captions only (skip auto-generated)
yt-dlp	Download audio + local Whisper transcription

Rules

• Always use --extract so that Claude performs the summarization rather than an external LLM.
• Pass --youtube auto unless the user requests a specific mode.
• If extraction fails, suggest the user try --youtube web or --youtube yt-dlp as fallbacks.
• For very long videos (> 2 hours), warn the user that the transcript may be truncated and offer to focus on specific sections.
• Do not install or modify the summarize package; assume summarize is already available on PATH.