Build and use your own MCP in Cursor in 5 minutes

1. Set up your project

mkdir cursor-mcp
cd cursor-mcp
npm init -y
npm pkg set type=module

2. Install dependencies

npm install @modelcontextprotocol/sdk

3. Create index.js

import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import { z } from "zod";

const server = new McpServer({
  name: "Hello World",
  version: "1.0.0"
});

server.tool("add",
  { a: z.number(), b: z.number() },
  async ({ a, b }) => ({
    content: [{ type: "text", text: String(a + b) }]
  })
);

const transport = new StdioServerTransport();
await server.connect(transport);

4. Add to Cursor

Go to Settings, MCP, and add new MCP server.

The command is node /absolute/path/to/your/index.js. For example node /Users/andyrewlee/mcp-server/index.js.

5. Trigger your MCP by asking Cursor to add 24 and 81

In Agent mode prompt 8 + 24 and watch the add tool in your MCP get triggered.

Comments

[danishlyy]

"cursor-mcp": {
"command": "node",
"args": [
"/Users/liyongyong/10-yingmi_application/mcp/cursor-mcp/index.js"
]
}

hello I configed above code in my cursor， but the

I donnot know where has problems

[Andrew Lee]

what happens if you run that in your terminal?

[danishlyy]

my cursor version is 0.47.8

[Andrew Lee]

github.com/andyrewlee/hello-world-...

[Aniket Singh]

For me, its throwing this error

[Andrew Lee]

does it show you what values were passed in for a and b values? another way to debug would be to run npx @modelcontextprotocol/inspector@latest and see if you have the same error.

[Daniel Bencz]

Are you in Composer and in Agent mode?