Alternatives to NotebookLM Skill

Claude Code skills are SKILL.md packages that extend the agent on demand. Custom slash commands merged into skills; follows the Agent Skills standard.

Google's source-grounded research notebook, now presented as Gemini Notebook at notebook.google. Analyzes your files and turns them into audio, video, and more.

Baoyu skill. Rechecked: folder is baoyu-post-to-wechat, MIT, 25,089 stars. Not leftover skills/post-to-wechat.