MCP Node Time

Instructions

Implementation Reference

• src/time-service.ts:83-168 (handler)

  Core handler implementing the timezone conversion logic: validates inputs, parses time/date, computes UTC adjustments, generates source/target timezone info including DST and offsets, and calculates time difference.
  static convertTime( sourceTimezone: string, targetTimezone: string, time: string, date?: string ): TimeConversionResult { this.validateTimezone(sourceTimezone); this.validateTimezone(targetTimezone); this.validateTime(time); const baseDate = date ? new Date(date) : new Date(); const [hours, minutes, seconds = 0] = time.split(':').map(Number); const sourceDate = new Date(baseDate); sourceDate.setHours(hours, minutes, seconds, 0); const sourceUTC = new Date(sourceDate.toLocaleString('en-US', { timeZone: 'UTC' })); const sourceLocal = new Date(sourceDate.toLocaleString('en-US', { timeZone: sourceTimezone })); const offset = sourceUTC.getTime() - sourceLocal.getTime(); const adjustedDate = new Date(sourceDate.getTime() + offset); const targetDate = new Date(adjustedDate.toLocaleString('en-US', { timeZone: targetTimezone })); const sourceInfo: TimezoneInfo = { timezone: sourceTimezone, datetime: sourceDate.toLocaleString('en-US', { timeZone: sourceTimezone, year: 'numeric', month: '2-digit', day: '2-digit', hour: '2-digit', minute: '2-digit', second: '2-digit', hour12: false }), isDST: this.isDaylightSavingTime(sourceDate, sourceTimezone), utcOffset: this.getUTCOffset(sourceDate, sourceTimezone), localizedFormat: sourceDate.toLocaleString('en-US', { timeZone: sourceTimezone, weekday: 'long', year: 'numeric', month: 'long', day: 'numeric', hour: '2-digit', minute: '2-digit', timeZoneName: 'short' }) }; const targetInfo: TimezoneInfo = { timezone: targetTimezone, datetime: targetDate.toLocaleString('en-US', { timeZone: targetTimezone, year: 'numeric', month: '2-digit', day: '2-digit', hour: '2-digit', minute: '2-digit', second: '2-digit', hour12: false }), isDST: this.isDaylightSavingTime(adjustedDate, targetTimezone), utcOffset: this.getUTCOffset(adjustedDate, targetTimezone), localizedFormat: adjustedDate.toLocaleString('en-US', { timeZone: targetTimezone, weekday: 'long', year: 'numeric', month: 'long', day: 'numeric', hour: '2-digit', minute: '2-digit', timeZoneName: 'short' }) }; const timeDifference = this.calculateTimeDifference( new Date(`2000-01-01T${time}`), targetDate ); return { source: sourceInfo, target: targetInfo, timeDifference }; }
• src/index.ts:46-71 (registration)

  MCP tool registration defining the 'convert_time' tool name, description, and JSON input schema matching the params.
  { name: 'convert_time', description: 'Convert time from one timezone to another', inputSchema: { type: 'object', properties: { sourceTimezone: { type: 'string', description: 'Source IANA timezone identifier', }, targetTimezone: { type: 'string', description: 'Target IANA timezone identifier', }, time: { type: 'string', description: 'Time in HH:MM or HH:MM:SS format (24-hour)', }, date: { type: 'string', description: 'Optional date in YYYY-MM-DD format. If not provided, uses current date', }, }, required: ['sourceTimezone', 'targetTimezone', 'time'], }, },
• src/interfaces.ts:20-25 (schema)

  TypeScript interface for ConvertTimeParams providing type safety for the tool parameters used in the handler.
  export interface ConvertTimeParams { sourceTimezone: string; targetTimezone: string; time: string; date?: string; }
• src/index.ts:131-149 (handler)

  MCP request handler switch case for 'convert_time': casts args to params, calls TimeService.convertTime, and returns JSON-formatted response.
  case 'convert_time': { const { sourceTimezone, targetTimezone, time, date } = (args as unknown) as ConvertTimeParams; const result = TimeService.convertTime(sourceTimezone, targetTimezone, time, date); return { content: [ { type: 'text', text: JSON.stringify({ conversion: { source: result.source, target: result.target, timeDifference: result.timeDifference, }, }, null, 2), }, ], }; }
• src/interfaces.ts:9-13 (schema)

  TypeScript interface for TimeConversionResult defining the output structure from the convertTime handler.
  export interface TimeConversionResult { source: TimezoneInfo; target: TimezoneInfo; timeDifference: string; }