Anthropic open-sourced the skills that power Claude's document features. 16 skills.

Most are examples. But 4 of them, PDF, DOCX, PPTX, XLSX, are the actual production code running behind Claude's "create a document" feature.
The 3 worth installing right now:
→ MCP Builder. Step-by-step guide for building Model Context Protocol servers. API research, tool naming, auth patterns, error handling.
→ Webapp Testing. Playwright-based toolkit with a decision tree. Server lifecycle manager. Screenshots, logs, the works.
→ Skill Creator. A skill for building skills. Draft, test, benchmark, optimize triggering. If you're building your own, start here.
They are not Claude-only. It's an open standard: OpenClaw, Cursor, GitHub Copilot, and the same SKILL format you can deploy on any agent.
And the architecture is smart. The agent only loads skill name + description into context.
Full instructions load only when needed. Linked files load only for edge cases. You're not burning tokens on skills you're not using.
How to install (2 minutes):
Claude Code:
> /plugin install document-skills@anthropic-agent-skills
OpenClaw:
> git clone anthropics/skills → ~/.openclaw/skills/
> symlink what you need → restart gateway