mcp-builder

name	mcp-builder
description	Build MCP (Model Context Protocol) servers in TypeScript or Python. Use when creating custom tools, resources, or prompts that extend AI assistant capabilities via MCP.
compatibility	Requires Node.js 18+ or Python 3.10+
metadata	{"version":"1.0"}

MCP Builder

Decision Tree

What are you building?
    ├─ Tool (action the AI can take) → Define tool with input schema
    ├─ Resource (data the AI can read) → Define resource with URI
    └─ Prompt (reusable template) → Define prompt with arguments

What language?
    ├─ TypeScript → See references/typescript-guide.md
    └─ Python → See references/python-guide.md

Quick Start (TypeScript)

npx @anthropic-ai/create-mcp-server my-server
cd my-server && npm install

import { McpServer } from '@anthropic-ai/mcp-server';

const server = new McpServer({ name: 'my-server', version: '1.0.0' });

server.tool('greet', { name: { type: 'string' } }, async ({ name }) => {
  return { content: [{ type: 'text', text: `Hello, ${name}!` }] };
});

server.run();

Quick Start (Python)

pip install mcp

from mcp.server import Server

server = Server("my-server")

@server.tool("greet")
async def greet(name: str) -> str:
    return f"Hello, {name}!"

server.run()

Configuration

Register in .claude/mcp.json:

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

Best Practices

• Return structured data (JSON) not just text
• Include error handling with meaningful messages
• Add input validation on all tool parameters
• Keep tools focused (one action per tool)
• Use descriptive names and descriptions (shown to the AI)

For detailed guides see:

• TypeScript MCP guide
• Python MCP guide