time-mcp

Instructions

Implementation Reference

• src/index.ts:40-56 (handler)

  Main handler for the 'current_time' tool call within the CallToolRequestSchema. Validates arguments using checkCurrentTimeArgs, computes the current time using getCurrentTime, and returns formatted response content.

  case 'current_time': {
    if (!checkCurrentTimeArgs(args)) {
      throw new Error(`Invalid arguments for tool: [${name}]`);
    }
  
    const { format, timezone } = args;
    const result = getCurrentTime(format, timezone);
    return {
      success: true,
      content: [
        {
          type: 'text',
          text: `Current UTC time is ${result.utc}, and the time in ${result.timezone} is ${result.local}.`,
        },
      ],
    };
  }

• src/tools.ts:3-33 (schema)

  Defines the Tool object for 'current_time', including name, description, and detailed inputSchema with properties for format and timezone.

  export const CURRENT_TIME: Tool = {
    name: 'current_time',
    description: 'Get the current date and time.',
    inputSchema: {
      type: 'object',
      properties: {
        format: {
          type: 'string',
          description: 'The format of the time, default is empty string',
          enum: [
            'h:mm A',
            'h:mm:ss A',
            'YYYY-MM-DD HH:mm:ss',
            'YYYY-MM-DD',
            'YYYY-MM',
            'MM/DD/YYYY',
            'MM/DD/YY',
            'YYYY/MM/DD',
            'YYYY/MM',
          ],
          default: 'YYYY-MM-DD HH:mm:ss',
        },
        timezone: {
          type: 'string',
          description: 'The timezone of the time, IANA timezone name, e.g. Asia/Shanghai',
          default: undefined,
        },
      },
      required: ['format'],
    },
  };

• src/index.ts:30-34 (registration)

  Registers the 'current_time' tool (via CURRENT_TIME export) in the tools list provided to clients via ListToolsRequest.

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

• src/index.ts:160-169 (helper)

  Helper function that computes current UTC time and local time in specified or guessed timezone, formatting as requested.

  function getCurrentTime(format: string, timezone?: string) {
    const utcTime = dayjs.utc();
    const localTimezone = timezone ?? dayjs.tz.guess();
    const localTime = dayjs().tz(localTimezone);
    return {
      utc: utcTime.format(format),
      local: localTime.format(format),
      timezone: localTimezone,
    };
  }

• src/index.ts:203-211 (helper)

  Type guard helper to validate arguments for the current_time tool.

  function checkCurrentTimeArgs(args: unknown): args is { format: string, timezone?: string } {
    return (
      typeof args === 'object' &&
      args !== null &&
      'format' in args &&
      typeof args.format === 'string' &&
      ('timezone' in args ? typeof args.timezone === 'string' : true)
    );
  }