An open packaging format for AI coding assistant extensions.

ccpkg is a self-contained archive format for packaging and distributing skills, agents, commands, hooks, MCP servers, and LSP servers as a single portable unit. One file, one install, zero post-install steps.

AI coding assistants are increasingly extensible, but sharing extensions is fragmented and unreliable. ccpkg solves this with a universal format built on open standards.

For extension authors: Package once, distribute everywhere. Your skills, MCP servers, and hooks ship as a single .ccpkg file that works across Claude Code, Gemini CLI, Codex, Copilot, and other compatible tools.

For users: Install extensions with confidence. Self-contained archives mean no dependency hell, no broken installs, and no minutes-long startup fetches. Lazy loading keeps your sessions fast.

For teams: Share curated extension sets with deterministic lockfiles. Project-scoped packages travel with the repo. User-scoped packages stay personal.

ccpkg composes existing specifications rather than replacing them:

Standard	Role
Agent Skills	Skill format (SKILL.md)
Model Context Protocol	MCP server configuration
Language Server Protocol	LSP server configuration
Semantic Versioning	Package versioning
JSON Schema	Manifest validation

• Specification --- the formal format definition
• Design Document --- rationale and decisions behind the design
• Manifest Schema --- machine-readable JSON Schema for manifest.json
• GitHub Repository --- source code and issue tracker

This specification is a draft (version 2026-02-14). Feedback and contributions are welcome via GitHub Issues.