mcp-builder Skill

Build high-quality MCP (Model Context Protocol) servers that enable Claude to interact with external services through well-designed tools.

What is MCP?

Model Context Protocol allows Claude to:

  • Call external APIs
  • Access databases
  • Read/write files
  • Interact with services
  • Execute tools
  • Fetch resources

When to Use

Use mcp-builder when creating MCP servers for:

  • Custom API integrations
  • Database access
  • File system operations
  • External service connections
  • Custom tools for Claude
  • Resource providers

Quick Start

Invoke the Skill

"Use mcp-builder to create MCP server for Stripe API with:
- Payment tools
- Subscription management
- Webhook handling
- TypeScript implementation"

What You Get

The skill will help you:

  1. Design server architecture
  2. Create tool definitions
  3. Implement handlers
  4. Add authentication
  5. Handle errors properly
  6. Write documentation
  7. Set up testing

Common Use Cases

API Integration

"Use mcp-builder to create MCP server for GitHub API:
- Repository management
- Issue tracking
- Pull request tools
- Authentication with tokens"

Database Access

"Use mcp-builder for PostgreSQL MCP server:
- Query execution
- Schema introspection
- Connection pooling
- Read-only safety"

File System

"Use mcp-builder to create file management MCP server:
- Read/write files
- Directory operations
- Search functionality
- Safe path handling"

Custom Tools

"Use mcp-builder for custom business logic:
- Invoice generation
- Report creation
- Data transformation
- Workflow automation"

MCP Server Types

Python (FastMCP)

"Use mcp-builder to create Python MCP server with FastMCP:
- Tool decorators
- Resource handlers
- Type hints
- Async operations"

Best for:

  • Data processing
  • ML/AI integration
  • Scientific computing
  • Python ecosystem tools

TypeScript (MCP SDK)

"Use mcp-builder to create TypeScript MCP server:
- Type safety
- Modern async/await
- NPM ecosystem
- Easy deployment"

Best for:

  • API wrappers
  • Web services
  • Node.js integrations
  • JavaScript tooling

Key Components

Tools

Functions Claude can call:

  • Input schema
  • Output format
  • Error handling
  • Documentation

Resources

Data Claude can read:

  • URIs
  • Content types
  • Dynamic updates
  • Metadata

Prompts

Templates Claude can use:

  • Pre-defined prompts
  • Parameter injection
  • Context building

Example Implementations

Stripe Integration

"Use mcp-builder to create Stripe MCP server with tools for:
- Create customer
- Create subscription
- Process payment
- Handle webhooks
- List transactions"

Slack Integration

"Use mcp-builder for Slack MCP server:
- Send messages
- List channels
- Search messages
- Upload files
- React to messages"

Database Tools

"Use mcp-builder for database MCP server:
- Execute queries
- Get schema info
- Run migrations
- Backup data
- Safety checks"

File Processing

"Use mcp-builder to create document processor:
- PDF extraction
- Image conversion
- Text analysis
- Format conversion"

Best Practices

Tool Design

The skill ensures:

  • Clear tool names
  • Descriptive parameters
  • Proper input validation
  • Good error messages
  • Complete documentation

Security

Implements:

  • Authentication
  • Authorization
  • Input sanitization
  • Rate limiting
  • Safe defaults

Error Handling

Provides:

  • Clear error messages
  • Proper error codes
  • Recovery suggestions
  • Logging
  • Graceful failures

Documentation

Creates:

  • Tool descriptions
  • Parameter docs
  • Usage examples
  • Setup guide
  • Troubleshooting

Advanced Features

Authentication

"Use mcp-builder to add authentication:
- API key validation
- OAuth2 flow
- Token refresh
- Session management"

Caching

"Use mcp-builder to implement caching:
- Response caching
- Cache invalidation
- TTL configuration
- Performance optimization"

Rate Limiting

"Use mcp-builder to add rate limiting:
- Per-user limits
- Endpoint limits
- Retry logic
- Backoff strategy"

Webhooks

"Use mcp-builder to handle webhooks:
- Signature verification
- Event processing
- Async handling
- Error recovery"

Development Workflow

1. Design Phase

"Use mcp-builder to design MCP server:
- Define tools needed
- Specify inputs/outputs
- Plan authentication
- Document API"

2. Implementation

"Use mcp-builder to implement:
- Create server structure
- Implement tools
- Add error handling
- Write tests"

3. Testing

"Use mcp-builder to test server:
- Unit tests for tools
- Integration tests
- Error scenarios
- Performance tests"

4. Deployment

"Use mcp-builder to deploy:
- Package server
- Configuration
- Monitoring
- Documentation"

Testing

Unit Tests

"Use mcp-builder to create tests for:
- Each tool function
- Error conditions
- Input validation
- Output format"

Integration Tests

"Use mcp-builder to test integration:
- Real API calls
- Authentication flow
- Error handling
- Edge cases"

Configuration

Claude Desktop

{
  "mcpServers": {
    "my-server": {
      "command": "node",
      "args": ["path/to/server.js"]
    }
  }
}

Environment Variables

"Use mcp-builder to configure:
- API keys
- Database URLs
- Service endpoints
- Feature flags"

Troubleshooting

Common Issues

Server not connecting

  • Check configuration path
  • Verify server starts
  • Review logs

Tools not appearing

  • Check tool definitions
  • Verify schema format
  • Review documentation

Authentication failing

  • Verify credentials
  • Check token format
  • Review auth flow

Quick Examples

Simple API Wrapper:

"Use mcp-builder to wrap REST API as MCP server"

Database Tools:

"Use mcp-builder for PostgreSQL query tools with read-only safety"

Custom Business Logic:

"Use mcp-builder to create MCP server for:
- Generate invoices
- Calculate taxes
- Send notifications
- Update records"

Multi-Service Integration:

"Use mcp-builder to combine:
- GitHub API
- Jira API
- Slack notifications
- Into single MCP server"

Resources

Next Steps

Bottom Line: mcp-builder creates production-ready MCP servers. Just describe the tools you need and the skill handles the implementation.