plugin-creator

Plugin Creator

Overview

Scaffolds new Claude Code plugins with proper directory structure, required files, marketplace catalog integration, and full validation. Supports all plugin types: command plugins, agent plugins, skill plugins, MCP server plugins, and hybrid combinations.

Prerequisites

• Write access to the plugins/ directory and .claude-plugin/marketplace.extended.json
• jq installed for JSON generation and validation
• pnpm run sync-marketplace available at the repository root
• ./scripts/validate-all-plugins.sh available for post-creation validation

Instructions

1. Gather requirements from the user request: plugin name (kebab-case), category (productivity, security, devops, testing, etc.), plugin type (commands, agents, skills, MCP, or combination), description, and keywords. Default author to the repository owner if unspecified (see ${CLAUDE_SKILL_DIR}/references/plugin-creation-process.md).
2. Create the plugin directory structure under plugins/[category]/[plugin-name]/:

   plugins/[category]/[plugin-name]/
   ├── .claude-plugin/
   │   └── plugin.json
   ├── README.md
   ├── LICENSE
   └── [commands/ | agents/ | skills/ | hooks/ | mcp/]
   

3. Generate .claude-plugin/plugin.json using the template from ${CLAUDE_SKILL_DIR}/references/file-templates.md. Populate all required fields: name, version (default 1.0.0), description, author (name and email), repository, license (default MIT), and keywords (minimum 2).
4. Generate README.md with installation instructions, usage examples, a description section, and contributor information.
5. Create a LICENSE file with MIT license text (or the specified license).
6. Generate component files based on the plugin type:
   • Commands: create commands/[command-name].md with proper YAML frontmatter (name, description, model).
   • Agents: create agents/[agent-name].md with YAML frontmatter including model field.
   • Skills: create skills/[skill-name]/SKILL.md with frontmatter (name, description, allowed-tools).
   • MCP: create package.json, tsconfig.json, src/index.ts, and .mcp.json.
7. Add the new plugin entry to .claude-plugin/marketplace.extended.json with matching name, version, category, description, source path, and keywords.
8. Run pnpm run sync-marketplace to regenerate marketplace.json.
9. Validate the new plugin by running ./scripts/validate-all-plugins.sh plugins/[category]/[plugin-name]/. Fix any reported issues before completion.

Output

A complete, CI-ready plugin containing:

• All required files (plugin.json, README.md, LICENSE)
• Component files matching the requested plugin type with proper frontmatter
• Marketplace catalog entry in marketplace.extended.json
• Synchronized marketplace.json
• Validation confirmation from validate-all-plugins.sh

Error Handling

Examples

Create a command plugin: Trigger: "Create a new security plugin called 'owasp-scanner' with commands." Process: Create plugins/security/owasp-scanner/ directory, generate plugin.json, README.md, LICENSE, and commands/scan.md with proper frontmatter. Add to marketplace, sync, validate (see ${CLAUDE_SKILL_DIR}/references/examples.md).

Scaffold a skills plugin: Trigger: "Scaffold a skills plugin for code review." Process: Create plugin directory with skills/code-review/SKILL.md containing trigger keywords for code review tasks. Generate plugin.json with appropriate keywords. Add to marketplace, sync, validate.

Create an MCP server plugin: Trigger: "Create a new MCP plugin for database queries." Process: Create plugins/mcp/db-query/ with package.json (including @modelcontextprotocol/sdk dependency), tsconfig.json, src/index.ts, .mcp.json, and standard files. Add to marketplace, sync, validate.

Resources

• ${CLAUDE_SKILL_DIR}/references/plugin-creation-process.md -- detailed creation workflow
• ${CLAUDE_SKILL_DIR}/references/file-templates.md -- templates for plugin.json, commands, agents, and skills
• ${CLAUDE_SKILL_DIR}/references/examples.md -- creation scenario walkthroughs
• ${CLAUDE_SKILL_DIR}/references/errors.md -- error handling patterns