youtube-summary

Summarize a YouTube video from its transcript into a concise Markdown note: a one- or two-sentence TL;DR, 4-6 key points with [m:ss] timestamps, and takeaways. The note is printed in chat and saved to a folder you configure, such as an Obsidian inbox.

The plugin is a portable Agent Plugin with one Agent Skill, so the same package works in Claude Code, Codex, Copilot CLI and opencode.

Requirements

uv. The transcript script declares its dependency (youtube-transcript-api) inline, so uv installs it on first use with no manual setup.
Network access to YouTube, and to PyPI on the first run.

Installation

Claude Code (Copilot CLI is the same with copilot in place of claude):

claude plugin marketplace add smykla-skalski/sai
claude plugin install youtube-summary@sai

Codex:

codex plugin marketplace add smykla-skalski/sai
codex plugin add youtube-summary@sai

opencode, or any agent that reads Agent Skills, loads skills/youtube-summary/ directly:

ln -s /path/to/sai/plugins/youtube-summary/skills/youtube-summary ~/.config/opencode/skills/youtube-summary

Local checkout: claude --plugin-dir /path/to/sai/plugins/youtube-summary/

Configuration

Set YOUTUBE_SUMMARY_DIR to an existing folder where notes should go, for example in your shell profile:

export YOUTUBE_SUMMARY_DIR="$HOME/Documents/Obsidian Vault/0_Inbox"

In Claude Code you can also set it under env in ~/.claude/settings.json. Notes are named YouTube - <title>.md; when another file already has that name, the video id (plus a counter if needed) is appended, so files that are not this video's summary are never overwritten.

When the variable is unset (or points to a missing folder), Claude Code asks where to save the note; other agents print it without saving. Summarizing the same video again replaces its earlier note.

Usage

In Claude Code and Copilot CLI use /youtube-summary, in Codex $youtube-summary, or just share a YouTube link and ask for a summary.

/youtube-summary https://www.youtube.com/watch?v=jNQXAC9IVRw
/youtube-summary https://youtu.be/jNQXAC9IVRw --no-save
/youtube-summary https://www.youtube.com/shorts/jNQXAC9IVRw --dir ~/notes/inbox

Flag	Purpose
(positional)	YouTube URL (`watch?v=`, `youtu.be/`, `/shorts/`, `/embed/`, `/live/`) or video id
`--no-save`	Print the note only
`--dir PATH`	Save to this existing folder instead of `YOUTUBE_SUMMARY_DIR`

An invalid URL, a video without a transcript, or an unavailable video ends with a clear message and no note.

How it works

skills/youtube-summary/scripts/fetch_transcript.py fetches the transcript (English preferred, otherwise the first available language) and the title and channel, and resolves the note path. It prints JSON and never writes the note; the agent writes the summary following skills/youtube-summary/references/output-template.md. Offline checks: uv run --script skills/youtube-summary/scripts/test_fetch_transcript.py.

The PEP 723 dependency block sits directly above the first function instead of at the top of the file; PEP 723 allows it anywhere, and that placement satisfies a comment-blocking pre-write hook.

License

MIT