Marketplace Creator

This skill provides comprehensive guidance for creating, managing, and validating Claude Code marketplace configurations.

About Marketplaces

Marketplaces are curated collections of plugins that can be distributed and installed together. A marketplace is defined by a marketplace.json file that lists available plugins with their sources, versions, and metadata.

What Marketplaces Provide

1. Plugin Discovery - Central catalog of related plugins
2. Version Management - Track plugin versions and updates
3. Easy Distribution - Users install from a single marketplace URL
4. Curation - Organize plugins by theme, purpose, or organization

Marketplace Development Workflow

Follow these steps when working with marketplaces:

1. Understand marketplace requirements and scope
2. Initialize marketplace configuration
3. Add plugins to the marketplace
4. Validate marketplace structure
5. Test marketplace installation
6. Distribute marketplace

Step 1: Understanding Marketplace Requirements

Before creating a marketplace, clarify:

• What plugins should be included?
• Who is the target audience (personal, team, public)?
• Will plugins be hosted on GitHub, local paths, or other sources?
• What categorization or organization makes sense?

Ask questions to gather concrete requirements:

• "What plugins should this marketplace include?"
• "Will this be for personal use, team distribution, or public sharing?"
• "Are the plugins already created, or do they need to be built?"
• "How should the plugins be categorized or grouped?"

Step 2: Initialize Marketplace Configuration

Create a new marketplace.json file with the required structure.

For detailed initialization steps:

• See references/marketplace-structure.md for complete setup instructions and field requirements
• Use the init_marketplace.py script for quick setup:

python3 skills/marketplace-creator/scripts/init_marketplace.py

The script will:

• Create marketplace.json with proper structure
• Prompt for owner name and email
• Add example plugin entry (to be customized)
• Include comments explaining each field

Minimum Required Fields:

{
  "name": "marketplace-name",
  "owner": {
    "name": "Owner Name",
    "email": "email@domain.com"
  },
  "description": "Marketplace description",
  "plugins": []
}

Step 3: Add Plugins to the Marketplace

Add plugin entries to the plugins array. Each plugin requires:

• name - Plugin identifier
• source - Where to find the plugin (GitHub, local path, URL)
• description - What the plugin does
• version - Semantic version (e.g., "1.0.0")
• author - Plugin author information

Helper script for adding plugins:

python3 skills/marketplace-creator/scripts/add_plugin_to_marketplace.py

For detailed plugin entry formats and source options:

• See references/marketplace-structure.md for all source format examples

Common Source Formats:

1. GitHub Repository (recommended for public plugins):

   "source": {
     "source": "github",
     "repo": "owner/repository"
   }
   

2. Relative Path (local installations only):

   "source": "./plugins/my-plugin"
   

3. Git Repository URL:

   "source": {
     "source": "url",
     "url": "https://gitlab.com/team/plugin.git"
   }
   

4. Direct Marketplace URL:

   "source": "https://example.com/path/to/marketplace.json"
   

Step 4: Validate Marketplace Structure

Use the validation script to check marketplace configuration:

python3 skills/marketplace-creator/scripts/validate_marketplace.py

The validator checks:

• JSON syntax validity
• Required fields are present
• Source format correctness (GitHub objects vs strings)
• No placeholder values remain
• Author format consistency
• Semantic versioning compliance

For complete validation checklist:

• See validation section in references/marketplace-structure.md

Step 5: Test Marketplace Installation

Test the marketplace locally before distribution:

# Install from local marketplace.json
claude plugin install /path/to/marketplace.json

# Or install specific plugin from marketplace
claude plugin install /path/to/marketplace.json --plugin plugin-name

Verify:

• All plugins install correctly
• Skills/commands/agents are available
• No configuration errors or warnings

Step 6: Distribute Marketplace

Choose distribution method:

Option 1: Git Repository

• Commit marketplace.json to repository
• Users install via: claude plugin install https://github.com/user/repo/marketplace.json

Option 2: Direct URL

• Host marketplace.json on web server
• Users install via: claude plugin install https://domain.com/marketplace.json

Option 3: Local/Team Distribution

• Share marketplace.json file or repository
• Users install from local path

Common Issues and Solutions

Issue: GitHub URL as String

Problem: GitHub repository URLs as strings are not supported in marketplace.json

// ❌ WRONG
"source": "https://github.com/username/plugin-name"

// ✅ CORRECT
"source": {
  "source": "github",
  "repo": "username/plugin-name"
}

Issue: Relative Paths for Public Distribution

Problem: Relative paths only work for local installations

// ⚠️ WARNING - local only
"source": "./plugins/my-plugin"

// ✅ CORRECT - for public distribution
"source": {
  "source": "github",
  "repo": "username/plugin-name"
}

Issue: Inconsistent Author Format

Problem: Author should use consistent object format

// ❌ WRONG - string format
"author": "Username"

// ✅ CORRECT - object format
"author": {
  "name": "Username"
}

Issue: Placeholder Values

Problem: Template placeholders must be replaced

// ❌ WRONG
"owner": {
  "name": "Your Name",
  "email": "your.email@example.com"
}

// ✅ CORRECT
"owner": {
  "name": "AnthonyKazyaka",
  "email": "anthony@domain.com"
}

Updating Existing Marketplaces

When updating an existing marketplace.json:

1. Adding a Plugin:

   • Use add_plugin_to_marketplace.py script
   • Or manually add entry to plugins array
   • Validate with validate_marketplace.py

2. Updating Plugin Version:

   • Locate plugin entry in plugins array
   • Update version field
   • Ensure plugin source reflects new version

3. Removing a Plugin:

   • Remove plugin entry from plugins array
   • Validate configuration

4. Reorganizing Plugins:

   • Consider creating multiple marketplace.json files
   • Or use plugin descriptions for categorization

Best Practices

• Use semantic versioning - Follow semver (major.minor.patch)
• Provide clear descriptions - Help users understand what each plugin does
• GitHub sources for public plugins - More reliable than direct URLs
• Test before distributing - Install marketplace locally first
• Version your marketplace - Track changes to marketplace itself
• Document plugin requirements - Note dependencies or prerequisites

For detailed structure information:

• See references/marketplace-structure.md for:
  • Complete marketplace.json schema
  • All source format options
  • Field requirements and validation rules
  • Example marketplace configurations

For step-by-step creation guidance:

• See references/marketplace-creation-process.md for:
  • Detailed workflow for each step
  • Decision trees for source format selection
  • Testing strategies
  • Distribution best practices

Resources

This skill includes:

• scripts/validate_marketplace.py - Automated validation script
• scripts/init_marketplace.py - Initialize new marketplace.json
• scripts/add_plugin_to_marketplace.py - Add plugin entries interactively
• references/marketplace-structure.md - Complete schema and examples
• references/marketplace-creation-process.md - Detailed step-by-step guide