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add-numbers.ts
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import { defineTool } from "@mcpexpress/core";
import { z } from "zod";

const InputSchema = z.object({
  a: z.number().describe("The first number"),
  b: z.number().describe("The second number"),
});

const OutputSchema = z.object({ sum: z.number() });

const add = ({ a, b }: z.infer<typeof InputSchema>) => ({
  sum: a + b,
});

export const addNumbers = defineTool({
  name: "add_numbers",
  title: "Add numbers",
  description: "Add two numbers together and return their sum.",
  input: InputSchema,
  output: OutputSchema,
  annotations: { readOnlyHint: true, openWorldHint: false },
  execute: (args) => add(args),
});