mcp-swiss

Instructions

Implementation Reference

• src/modules/energy.ts:202-253 (handler)

  The implementation of the get_electricity_tariff tool handler, which processes the input arguments, fetches data from the ElCom GraphQL API, and formats the response.

  switch (name) {
    case "get_electricity_tariff": {
      const municipality = args.municipality as string;
      const category = (args.category as string | undefined) ?? "H4";
      const year = (args.year as string | undefined) ?? CURRENT_YEAR;
  
      if (!municipality?.trim()) {
        throw new Error("municipality is required. Use search_municipality_energy to find the BFS number.");
      }
  
      const raw = await getTariffWithComponents(municipality, category, year);
      const observations = raw.observations as Array<Record<string, unknown>>;
  
      if (!observations.length) {
        return JSON.stringify({
          error: "No tariff data found",
          municipality,
          category,
          year,
          hint: "Check the municipality BFS number with search_municipality_energy. Not all municipalities have tariff data for every year.",
          source: "https://www.strompreis.elcom.admin.ch",
        }, null, 2);
      }
  
      // If multiple operators, return all (some municipalities served by multiple operators)
      const result = observations.map((obs) => ({
        municipality: obs.municipalityLabel,
        municipalityId: obs.municipality,
        canton: obs.cantonLabel,
        operator: obs.operatorLabel,
        category,
        categoryDescription: CATEGORY_DESCRIPTIONS[category] ?? category,
        year,
        tariff: {
          total_rp_per_kwh: obs.total,
          components: {
            energy_rp_per_kwh: obs.energy,
            grid_usage_rp_per_kwh: obs.gridusage,
            municipality_charge_rp_per_kwh: obs.charge,
            federal_levy_rp_per_kwh: obs.aidfee,
            fixed_costs_rp_per_kwh: obs.fixcosts,
            metering_rate_rp_per_kwh: obs.meteringrate,
            annual_metering_cost_rp_per_kwh: obs.annualmeteringcost,
          },
        },
        coverageRatio: obs.coverageRatio,
        note: "Prices in Rappen per kWh (1 CHF = 100 Rappen)",
        source: `https://www.strompreis.elcom.admin.ch/municipality/${municipality}`,
      }));
  
      return JSON.stringify(result.length === 1 ? result[0] : result, null, 2);
    }

• src/modules/energy.ts:85-111 (schema)

  Tool definition and input schema for get_electricity_tariff.

  export const energyTools = [
    {
      name: "get_electricity_tariff",
      description:
        "Get Swiss electricity tariff (price in Rappen/kWh) for a municipality from ElCom (Swiss Federal Electricity Commission). Returns total price and price breakdown by component (energy, grid, taxes). Valid years: 2011–2026.",
      inputSchema: {
        type: "object",
        required: ["municipality"],
        properties: {
          municipality: {
            type: "string",
            description:
              "Municipality BFS number (e.g. '261' for Zürich, '351' for Bern, '6621' for Genève). Use search_municipality_energy to find the ID.",
          },
          category: {
            type: "string",
            description:
              "Electricity category. Household: H1–H8 (H4 is default, ~4500 kWh/year). Commercial: C1–C7. Default: H4.",
            enum: ["H1","H2","H3","H4","H5","H6","H7","H8","C1","C2","C3","C4","C5","C6","C7"],
          },
          year: {
            type: "string",
            description: "Tariff year (2011–2026). Default: current year (2026).",
          },
        },
      },
    },

• src/modules/energy.ts:159-194 (helper)

  Helper function getTariffWithComponents that encapsulates the GraphQL query logic for fetching electricity tariffs.

  async function getTariffWithComponents(municipality: string, category: string, year: string): Promise<Record<string, unknown>> {
    // Fetch all price components via aliased query
    const query = `
      query ObservationsWithAllPriceComponents($locale: String!, $filters: ObservationFilters!) {
        observations(locale: $locale, filters: $filters) {
          period
          municipality
          municipalityLabel
          operator
          operatorLabel
          canton
          cantonLabel
          category
          total: value(priceComponent: total)
          energy: value(priceComponent: energy)
          gridusage: value(priceComponent: gridusage)
          charge: value(priceComponent: charge)
          aidfee: value(priceComponent: aidfee)
          fixcosts: value(priceComponent: fixcosts)
          meteringrate: value(priceComponent: meteringrate)
          annualmeteringcost: value(priceComponent: annualmeteringcost)
        }
      }
    `;
  
    const data = await gql<{ observations: Array<Record<string, unknown>> }>(query, {
      locale: "de",
      filters: {
        period: [year],
        municipality: [municipality],
        category: [category],
      },
    });
  
    return { observations: data.observations ?? [] };
  }