Agent Skills, MCP servers and Claude Code plugins.
skills/ one directory each - SKILL.md + optional scripts/ references/ assets/
mcp/ one server.json each
plugins/ only when the unit is MORE than a skill
| Layer | Spec | Validator |
|---|---|---|
| skills | agentskills.io | skills-ref validate ./<skill> |
| MCP servers | MCP registry server.json |
check-jsonschema |
| plugins | Claude Code marketplaces | claude plugin validate |
Add as a marketplace:
/plugin marketplace add izzykatt/ai