Building Custom MCP Servers for Cursor IDE

Step-by-step tutorial for creating custom MCP servers to extend Cursor with proprietary databases, internal APIs, and custom developer tools.

MCP servers let you connect custom data sources and make them available inside Cursor for AI-enhanced development.

Why Build Custom MCP Servers?

Connect context from:

• Proprietary databases and data warehouses
• Internal documentation systems
• Custom monitoring and observability tools
• CI/CD pipeline status
• Error and system logs

Getting Started

Step 1: Install the MCP SDK

npm install @modelcontextprotocol/sdk

Step 2: Define Server Capabilities

Choose what your server provides: tools, resources, or prompts.

Step 3: Implement Handlers

Write handler functions for each capability.

Step 4: Configure in Cursor

Add your server to Cursor Settings > Tools & MCP.

Server Types

• Stdio: Runs locally, communicates via stdin/stdout (simplest to develop)
• HTTP: Independent process, multiple client connections (production-ready)

Example: Database MCP Server

Expose table schemas, run read-only queries, and provide data context to Agent mode for database-aware code generation.

Example: Error Log MCP Server

Monitor application logs and surface recent errors during debugging sessions.

Best Practices

• Keep servers focused on a single concern
• Implement proper error handling and timeouts
• Add rate limiting for external API calls
• Document available tools clearly
• Version your MCP servers alongside your codebase
• Test thoroughly with different prompt scenarios