mcp-builder

# MCP Builder Build a working MCP server from a description of the tools you need. Produces a deployable Python server using FastMCP. ## Workflow ### Step 1: Define What to Expose Ask what the server needs to provide: - **Tools** -- Functions Claude can call (API wrappers, calculations, file operations) - **Resources** -- Data Claude can read (database records, config, documents) - **Prompts** -- Reusable prompt templates with parameters A brief like "MCP server for querying our customer database" is enough. ### Step 2: Scaffold the Server ```bash pip install fastmcp ``` Create the server file. The server instance MUST be at module level: ```python from fastmcp import FastMCP # MUST be at module level for FastMCP Cloud mcp = FastMCP("My Server") @mcp.tool() async def search_customers(query: str) -> str: """Search customers by name or email.""" # Implementation here return f"Found customers matching: {query}" @mcp.resource("customers://{customer_id}") async def get_customer(customer_id: str) -> str: """Get customer details by ID.""" return f"Customer {customer_id} details" if __name__ == "__main__": mcp.run() ``` ### Step 3: Add Companion CLI Scripts (Optional) For Claude Code terminal use, add scripts alongside the MCP server: ``` my-mcp-server/ ├── src/index.ts # MCP server (for Claude.ai) ├── scripts/ │ ├── search.ts # CLI version of search tool │ └── _shared.ts # Shared auth/config ├── SCRIPTS.md ...