time-mcp

Instructions

Implementation Reference

• src/index.ts:74-90 (handler)

  Main handler logic for the 'days_in_month' tool call within the MCP server request handler. Validates arguments, computes the result using getDaysInMonth, and returns a formatted response.

  case 'days_in_month': {
    if (!checkDaysInMonthArgs(args)) {
      throw new Error(`Invalid arguments for tool: [${name}]`);
    }
  
    const date = args.date;
    const result = getDaysInMonth(date);
    return {
      success: true,
      content: [
        {
          type: 'text',
          text: `The number of days in month is ${result}.`,
        },
      ],
    };
  }

• src/tools.ts:50-62 (schema)

  Tool schema definition for 'days_in_month', including name, description, and input schema.

  export const DAYS_IN_MONTH: Tool = {
    name: 'days_in_month',
    description: 'Get the number of days in a month. If no date is provided, get the number of days in the current month.',
    inputSchema: {
      type: 'object',
      properties: {
        date: {
          type: 'string',
          description: 'The date to get the days in month. Format: YYYY-MM-DD',
        },
      },
    },
  };

• src/index.ts:179-181 (helper)

  Core helper function that calculates the number of days in a given month (or current month) using dayjs library.

  function getDaysInMonth(date?: string) {
    return date ? dayjs(date).daysInMonth() : dayjs().daysInMonth();
  }

• src/index.ts:30-34 (registration)

  Registration of the 'days_in_month' tool (via DAYS_IN_MONTH) in the server's list tools handler.

  server.setRequestHandler(ListToolsRequestSchema, async () => {
    return {
      tools: [CURRENT_TIME, RELATIVE_TIME, DAYS_IN_MONTH, GET_TIMESTAMP, CONVERT_TIME, GET_WEEK_YEAR],
    };
  });

• src/index.ts:222-229 (helper)

  Input validation helper function for 'days_in_month' tool arguments.

  function checkDaysInMonthArgs(args: unknown): args is { date: string } {
    return (
      typeof args === 'object' &&
      args !== null &&
      'date' in args &&
      typeof args.date === 'string'
    );
  }