noaa-tidesandcurrents-mcp

Instructions

Implementation Reference

• src/tools/derived-product-tools.ts:42-52 (handler)

  The MCP tool handler (execute function) that calls the DpapiService method and returns the JSON-stringified result, with error handling.

  execute: async (params) => {
    try {
      const result = await dpapiService.getExtremeWaterLevels(params);
      return JSON.stringify(result);
    } catch (error) {
      if (error instanceof Error) {
        throw new Error(`Failed to get extreme water levels: ${error.message}`);
      }
      throw new Error('Failed to get extreme water levels');
    }
  }

• src/schemas/dpapi.ts:22-26 (schema)

  Zod schema defining the input parameters for the get_extreme_water_levels tool (station, units, format).

  export const ExtremeWaterLevelsSchema = z.object({
    station: StationSchema,
    units: UnitsSchema,
    format: FormatSchema
  }).describe('Get extreme water levels for a station');

• src/tools/derived-product-tools.ts:38-53 (registration)

  Registration of the get_extreme_water_levels tool on the FastMCP server, including name, description, input schema, and handler.

  server.addTool({
    name: 'get_extreme_water_levels',
    description: 'Get extreme water levels and exceedance probabilities for a station',
    parameters: ExtremeWaterLevelsSchema,
    execute: async (params) => {
      try {
        const result = await dpapiService.getExtremeWaterLevels(params);
        return JSON.stringify(result);
      } catch (error) {
        if (error instanceof Error) {
          throw new Error(`Failed to get extreme water levels: ${error.message}`);
        }
        throw new Error('Failed to get extreme water levels');
      }
    }
  });

• src/services/dpapi-service.ts:71-80 (helper)

  Supporting service method in DpapiService that constructs and fetches from the NOAA DPAPI '/ewl' endpoint for extreme water levels data.

  async getExtremeWaterLevels(params: Record<string, any>): Promise<any> {
    const { station, units = 'english', format = 'json', ...rest } = params;
    
    return this.fetchDpapi('/ewl', {
      station,
      units,
      format,
      ...rest
    });
  }