Claude Code Plugin Architecture

Overview

Claude Code has a plugin system with 4 extension points: skills (auto-activating knowledge), commands (slash commands), agents (specialized sub-agents), and MCP servers (tool providers). This skill covers building all four.

Prerequisites

• A supported Claude Code environment and an isolated plugin workspace
• A declared ownership boundary for filesystem, network, and credential access
• Validation tooling for manifests, skill metadata, commands, agents, and MCP
• A rollback plan that can disable a plugin without deleting user state

Instructions

Start with the smallest extension point that meets the requirement, declare only the tools and permissions it needs, and validate it locally before adding it to a marketplace or shared environment. Test discovery, activation, failure, and rollback paths; do not expose secrets through examples, environment files, logs, or MCP response payloads.