Fake Store API MCP Server

Instructions

Implementation Reference

• src/tools/carts.ts:32-36 (handler)

  Handler function that executes the core logic of fetching a single cart by ID from the Fake Store API, including input validation.

  export async function getCartById(args: { id: number }): Promise<Cart> {
    const { id } = args;
    validatePositiveInteger(id, 'Cart ID');
    return get<Cart>(`/carts/${id}`);
  }

• src/tools/carts.ts:138-151 (schema)

  Input schema definition for the fakestore_get_cart tool, specifying the required 'id' parameter.

  {
    name: 'fakestore_get_cart',
    description: 'Get a single cart by its ID',
    inputSchema: {
      type: 'object',
      properties: {
        id: {
          type: 'number',
          description: 'Cart ID',
        },
      },
      required: ['id'],
    },
  },

• src/index.ts:124-129 (registration)

  Registration and dispatch logic in the main CallToolRequest handler that matches the tool name and invokes the getCartById handler.

  if (name === 'fakestore_get_cart') {
    const result = await getCartById(args as { id: number });
    return {
      content: [{ type: 'text', text: JSON.stringify(result, null, 2) }],
    };
  }

• src/index.ts:40-44 (registration)

  Tool listing handler that includes cartTools (containing the fakestore_get_cart schema) in the list of available tools.

  server.setRequestHandler(ListToolsRequestSchema, async () => {
    return {
      tools: [...productTools, ...cartTools, ...userTools],
    };
  });