Time Tools MCP Server

Instructions

Implementation Reference

• src/index.ts:151-167 (handler)

  Handler function that calculates the elapsed time between two datetimes using dayjs.diff, with validation for valid dates.

  async ({ from, to, unit = "second" }) => {
      const fromDateTime = dayjs(from);
      const toDateTime = dayjs(to);
      if (!fromDateTime.isValid() || !toDateTime.isValid()) {
          return {
              content: [{ type: "text", text: "Invalid format" }],
              isError: true,
          };
      }
      /**
       * {@link https://day.js.org/docs/en/display/difference}
       */
      const duration = toDateTime.diff(fromDateTime, unit, true);
      return {
          content: [{ type: "text", text: String(duration) }],
      };
  },

• src/index.ts:134-150 (schema)

  Input schema using Zod for the from datetime, to datetime, and optional unit (defaults to millisecond).

  {
      from: z.string(),
      to: z.string(),
      unit: z
          .enum([
              "millisecond",
              "second",
              "minute",
              "hour",
              "day",
              "week",
              "month",
              "year",
          ])
          .optional()
          .default("millisecond"),
  },

• src/index.ts:131-168 (registration)

  Registration of the get_elapsed_time tool using server.tool, including description, input schema, and inline handler.

  server.tool(
      "get_elapsed_time",
      "Get the difference time between two datetimes (e.g. 2025-01-01 01:01:01 and 2025-01-02 02:02:02)",
      {
          from: z.string(),
          to: z.string(),
          unit: z
              .enum([
                  "millisecond",
                  "second",
                  "minute",
                  "hour",
                  "day",
                  "week",
                  "month",
                  "year",
              ])
              .optional()
              .default("millisecond"),
      },
      async ({ from, to, unit = "second" }) => {
          const fromDateTime = dayjs(from);
          const toDateTime = dayjs(to);
          if (!fromDateTime.isValid() || !toDateTime.isValid()) {
              return {
                  content: [{ type: "text", text: "Invalid format" }],
                  isError: true,
              };
          }
          /**
           * {@link https://day.js.org/docs/en/display/difference}
           */
          const duration = toDateTime.diff(fromDateTime, unit, true);
          return {
              content: [{ type: "text", text: String(duration) }],
          };
      },
  );