Announced September 30, 2026, Gemini app Skills are custom instruction packs (optional PDFs, images, and other reference files) that Gemini can auto-apply or that you trigger with / plus the skill name. They run in gemini.google.com chat, the Gemini mobile app, and the Mac app. They are not agent SKILL.md playbooks for Claude Code or Cursor, even though Google accepts a SKILL.md upload as an import format. Gems auto-migrate later; Skills do not sync between the Gemini app and Workspace.