import { McpServer, type McpTool } from 'simple-mcp';
import { z } from 'zod';
// Initialize a new MCP server with the name 'calculator-server'
const server = new McpServer({ name: 'calculator-server', version: '1.0.0' });
// Define a new tool named 'calculator'
const tool: McpTool = {
name: 'calculator',
// Specify the expected input parameters for the tool
parameters: {
operation: z
.enum(['add', 'subtract', 'multiply', 'divide'])
.describe('Mathematical operation to perform'),
a: z.number().describe('First number'),
b: z.number().describe('Second number'),
},
// Define the logic to be executed when the tool is called
execute: async ({ operation, a, b }) => {
let result = 0; // Initialize with default value
let symbol = ''; // Initialize with default value
// Perform the requested operation
switch (operation) {
case 'add':
result = a + b;
symbol = '+';
break;
case 'subtract':
result = a - b;
symbol = '-';
break;
case 'multiply':
result = a * b;
symbol = '*';
break;
case 'divide':
if (b === 0) {
throw new Error('Division by zero is not allowed');
}
result = a / b;
symbol = '/';
break;
}
// Return the result
return {
content: [
{
type: 'text',
text: `${a} ${symbol} ${b} = ${result}`,
},
],
};
},
};
// Register the tool with the server
server.tool(tool);
// Start the server using stdio as the transport method
server.start({ transportType: 'stdio' });
