youtube-summary

name	youtube-summary
description	Summarize YouTube videos into structured Markdown with youtube2md, including chaptered notes, timestamp links, and key takeaways. Use when the user provides one or more YouTube URLs and asks for summaries, study notes, language-specific summaries, transcript extraction, or machine-readable JSON output.
env	[{"name":"OPENAI_API_KEY","required":false,"description":"Enables full summarization mode. When set, transcript content is sent to OpenAI. Omit to use extract-only mode with local summarization."}]

YouTube Summary (youtube2md)

Use the official youtube2md CLI behavior from the repository.

Runtime + security prerequisites

• Require Node.js 18+.
• Require preinstalled youtube2md on PATH.
  • Recommended pinned install: npm i -g youtube2md@1.0.1
• Require python3 for transcript text preparation (prepare.py) in extract mode.
• Default runner uses local youtube2md executable only.
• Runtime npm execution (npx) is intentionally not supported in this skill.
• The YOUTUBE2MD_BIN environment variable override is rejected by the runner.
• OPENAI_API_KEY enables full summarization mode; transcript/content may be sent to OpenAI through youtube2md’s workflow.
  • For sensitive content, omit OPENAI_API_KEY and use extract mode.
• In sensitive environments, audit the upstream youtube2md package and dependencies before installation or version bumps.

See references/security.md before first-time install/enable.

Workflow

1. Validate input

   • Accept youtube.com and youtu.be URLs.
   • If URLs are missing, ask for one URL per line.

2. Choose mode

   • Full mode: generates Markdown.
     • Use when OPENAI_API_KEY is available and external API use is acceptable.
   • Extract mode (--extract-only): outputs transcript JSON and prepares transcript text (.txt).
     • Use when API key is unavailable or when transcript-only output is requested.
   • Prefer a no-error path: check key first and run extract directly when key is missing.

3. Run converter

   • Preferred runner script:
     • scripts/run_youtube2md.sh <url> full [output_md_path] [language] [model]
       • If OPENAI_API_KEY is missing, runner auto-falls back to extract mode by default.
     • scripts/run_youtube2md.sh <url> extract [output_json_path]
   • Optional machine-readable CLI output:
     • YOUTUBE2MD_JSON=1 scripts/run_youtube2md.sh <url> full
     • YOUTUBE2MD_JSON=1 scripts/run_youtube2md.sh <url> extract
   • Runtime controls:
     • Use only locally installed youtube2md executable.
     • Do not use runtime npm execution (npx) for this skill.
   • Direct CLI equivalent:
     • youtube2md --url <url> [--out <path>] [--lang <language>] [--model <model>]
     • Add --extract-only for transcript-only mode.

4. Verify output

   • Full mode: Markdown file exists and is non-empty.
   • Extract mode: JSON file exists and is non-empty.
   • Extract mode: prepared TXT file exists and is non-empty.
   • If using --json, parse ok: true/false and handle error code.

5. Respond to the user

   • Follow references/output-format.md as the default response shape.
   • Follow references/summarization-behavior.md for source policy and chapter/takeaway density.

Multi-video requests

• Process URLs sequentially.
• Return per-video summary results (omit local file paths unless requested).
• If any fail, report successful items first, then failures with fixes.

Built-in behavior to trust

• Default output paths:
  • Full mode: ./summaries/<video_id>.md
  • Extract mode: ./summaries/<video_id>.json
  • Local runner post-process (extract): ./summaries/<video_id>.txt via prepare.py

Packaging hygiene

• Do not publish generated outputs (e.g., summaries/*.json, summaries/*.txt) inside the skill folder.
• Keep only source files (SKILL.md, scripts/, references/, helpers) in release artifacts.

Resources

• CLI runner: scripts/run_youtube2md.sh
• Transcript text prep: prepare.py
• Output guidance: references/output-format.md
• Behavior reference: references/summarization-behavior.md
• Security/install notes: references/security.md
• Troubleshooting and error codes: references/troubleshooting.md