import type { CallToolResult, McpServer } from '@modelcontextprotocol/server';
import * as z from 'zod/v4';
const inputSchema = z.object({
numbers: z.array(z.number()).min(1).max(100).describe('Numbers to add together.'),
});
const outputSchema = z.object({
sum: z.number(),
count: z.number().int().positive(),
});
export function register(server: McpServer): void {
server.registerTool(
'sum_numbers',
{
title: 'Sum Numbers',
description: 'Add a list of numbers and return sum + count.',
inputSchema,
outputSchema,
annotations: {
readOnlyHint: true,
idempotentHint: true,
},
},
async ({ numbers }, ctx): Promise<CallToolResult> => {
const sum = numbers.reduce((total, value) => total + value, 0);
await ctx.mcpReq.log('debug', { tool: 'sum_numbers', count: numbers.length, sum });
return {
content: [
{
type: 'text',
text: `Sum(${numbers.join(', ')}) = ${sum}`,
},
],
structuredContent: {
sum,
count: numbers.length,
},
};
},
);
}
