get_moon_phase
Retrieve moon phase details for a specific date and location using NOAA data. Input date, latitude, longitude, and choose output format (json/text).
Instructions
Get moon phase information for a specific date
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| date | No | Date to get moon phase for (YYYY-MM-DD format). Defaults to current date. | |
| format | No | Output format (json or text) | |
| latitude | No | Latitude for location-specific calculations | |
| longitude | No | Longitude for location-specific calculations |
Implementation Reference
- src/tools/moon-tools.ts:18-31 (handler)The execute handler for the 'get_moon_phase' tool. It invokes the moon phase service, formats the output as text or JSON based on the 'format' parameter, and handles errors.execute: async (params) => { try { const result = moonPhaseService.getMoonPhase(params); if (params.format === 'text') { return `Moon phase for ${result.date}: ${result.phaseName} (${(result.illumination * 100).toFixed(1)}% illuminated)`; } return JSON.stringify(result); } catch (error) { if (error instanceof Error) { throw new Error(`Failed to get moon phase: ${error.message}`); } throw new Error('Failed to get moon phase'); } }
- src/interfaces/moon.ts:7-12 (schema)Zod schema defining the input parameters for the 'get_moon_phase' tool.export const MoonPhaseParamsSchema = z.object({ date: z.string().optional().describe('Date to get moon phase for (YYYY-MM-DD format). Defaults to current date.'), latitude: z.number().min(-90).max(90).optional().describe('Latitude for location-specific calculations'), longitude: z.number().min(-180).max(180).optional().describe('Longitude for location-specific calculations'), format: z.enum(['json', 'text']).optional().describe('Output format (json or text)') });
- src/tools/moon-tools.ts:14-32 (registration)Registration of the 'get_moon_phase' tool on the MCP server, specifying name, description, parameters schema, and execute handler.server.addTool({ name: 'get_moon_phase', description: 'Get moon phase information for a specific date', parameters: MoonPhaseParamsSchema, execute: async (params) => { try { const result = moonPhaseService.getMoonPhase(params); if (params.format === 'text') { return `Moon phase for ${result.date}: ${result.phaseName} (${(result.illumination * 100).toFixed(1)}% illuminated)`; } return JSON.stringify(result); } catch (error) { if (error instanceof Error) { throw new Error(`Failed to get moon phase: ${error.message}`); } throw new Error('Failed to get moon phase'); } } });
- Core helper function in MoonPhaseService that computes detailed moon phase information using SunCalc library for illumination, position, phase name, age, distance, etc.getMoonPhase(params: MoonPhaseParams): MoonPhaseInfo { const date = params.date ? new Date(params.date) : new Date(); // Get moon illumination data const illuminationData = SunCalc.getMoonIllumination(date); // Get moon position data (requires location) const latitude = params.latitude ?? 0; const longitude = params.longitude ?? 0; const positionData = SunCalc.getMoonPosition(date, latitude, longitude); // Calculate moon phase name const phaseName = this.getMoonPhaseName(illuminationData.phase); // Calculate if the moon is waxing (increasing illumination) const isWaxing = illuminationData.phase < 0.5; // Calculate approximate moon age (0-29.53 days) const lunarMonth = 29.53; // days const age = illuminationData.phase * lunarMonth; // Calculate apparent diameter (in degrees) const diameter = 0.5181 * (384400 / positionData.distance); return { date: date.toISOString().split('T')[0], phase: illuminationData.phase, phaseName, illumination: illuminationData.fraction, age, distance: positionData.distance, diameter, isWaxing }; }