Plugin System

Source: src/plugins/ — builtinPlugins.ts, bundled/

Overview

The plugin system provides an extension point for adding functionality to Claude Code beyond what tools and skills offer. Plugins can hook into the application lifecycle and modify behavior.

Architecture

Plugins are registered through builtinPlugins.ts and loaded during application initialization. Each plugin can:

Register new tools
Add event listeners
Modify the rendering pipeline
Extend the command system

Bundled Plugins

Bundled plugins are shipped with Claude Code in src/plugins/bundled/. These provide core functionality that is implemented as plugins for modularity.

Plugin API

Plugins interact with Claude Code through a defined API that provides access to:

Application state
Tool registry
Event system
Configuration

Relationship to MCP

While MCP servers provide external tool integration via a standardized protocol, plugins operate within the Claude Code process itself. Plugins have deeper access to the application internals compared to MCP servers.