Plugin Dev

A comprehensive toolkit for developing Claude Code plugins with expert guidance on hooks, MCP integration, plugin structure, and marketplace publishing.

Overview

The plugin-dev toolkit provides seven specialized skills to help you build high-quality Claude Code plugins:

1. hook-development - Advanced hooks API and event-driven automation
2. mcp-integration - Model Context Protocol server integration
3. plugin-structure - Plugin organization and manifest configuration
4. plugin-settings - Configuration patterns using .claude/plugin-name.local.md files
5. command-development - Creating slash commands with frontmatter and arguments
6. agent-development - Creating autonomous agents with AI-assisted generation
7. skill-development - Creating skills with progressive disclosure and strong triggers

Each skill follows best practices with progressive disclosure: lean core documentation, detailed references, working examples, and utility scripts.

Guided Workflow Command

/plugin-dev:create-plugin

A comprehensive, end-to-end workflow command for creating plugins from scratch, similar to the feature-dev workflow.

8-Phase Process:

1. Discovery - Understand plugin purpose and requirements
2. Component Planning - Determine needed skills, commands, agents, hooks, MCP
3. Detailed Design - Specify each component and resolve ambiguities
4. Structure Creation - Set up directories and manifest
5. Component Implementation - Create each component using AI-assisted agents
6. Validation - Run plugin-validator and component-specific checks
7. Testing - Verify plugin works in Claude Code
8. Documentation - Finalize README and prepare for distribution

Features:

• Asks clarifying questions at each phase
• Loads relevant skills automatically
• Uses agent-creator for AI-assisted agent generation
• Runs validation utilities (validate-agent.sh, validate-hook-schema.sh, etc.)
• Follows plugin-dev's own proven patterns
• Guides through testing and verification

Usage:

/plugin-dev:create-plugin [optional description]

# Examples:
/plugin-dev:create-plugin
/plugin-dev:create-plugin A plugin for managing database migrations

Use this workflow for structured, high-quality plugin development from concept to completion.

Skills

1. hook-development

Trigger phrases: "create a hook", "add a PreToolUse hook", "validate tool use", "implement prompt-based hooks", "${CLAUDE_PLUGIN_ROOT}", "block dangerous commands"

What it covers:

• Prompt-based hooks (recommended) with LLM decision-making
• Command hooks for deterministic validation
• All hook events: PreToolUse, PostToolUse, Stop, SubagentStop, SessionStart, SessionEnd, UserPromptSubmit, PreCompact, Notification
• Hook output formats and JSON schemas
• Security best practices and input validation
• ${CLAUDE_PLUGIN_ROOT} for portable paths

Resources:

• Core SKILL.md (1,619 words)
• 3 example hook scripts (validate-write, validate-bash, load-context)
• 3 reference docs: patterns, migration, advanced techniques
• 3 utility scripts: validate-hook-schema.sh, test-hook.sh, hook-linter.sh

Use when: Creating event-driven automation, validating operations, or enforcing policies in your plugin.

2. mcp-integration

Trigger phrases: "add MCP server", "integrate MCP", "configure .mcp.json", "Model Context Protocol", "stdio/SSE/HTTP server", "connect external service"

What it covers:

• MCP server configuration (.mcp.json vs plugin.json)
• All server types: stdio (local), SSE (hosted/OAuth), HTTP (REST), WebSocket (real-time)
• Environment variable expansion (${CLAUDE_PLUGIN_ROOT}, user vars)
• MCP tool naming and usage in commands/agents
• Authentication patterns: OAuth, tokens, env vars
• Integration patterns and performance optimization

Resources:

• Core SKILL.md (1,666 words)
• 3 example configurations (stdio, SSE, HTTP)
• 3 reference docs: server-types (~3,200w), authentication (~2,800w), tool-usage (~2,600w)

Use when: Integrating external services, APIs, databases, or tools into your plugin.

3. plugin-structure

Trigger phrases: "plugin structure", "plugin.json manifest", "auto-discovery", "component organization", "plugin directory layout"

What it covers:

• Standard plugin directory structure and auto-discovery
• plugin.json manifest format and all fields
• Component organization (commands, agents, skills, hooks)
• ${CLAUDE_PLUGIN_ROOT} usage throughout
• File naming conventions and best practices
• Minimal, standard, and advanced plugin patterns

Resources:

• Core SKILL.md (1,619 words)
• 3 example structures (minimal, standard, advanced)
• 2 reference docs: component-patterns, manifest-reference

Use when: Starting a new plugin, organizing components, or configuring the plugin manifest.