mcp-swiss

Instructions

Implementation Reference

• src/modules/post.ts:267-302 (handler)

  The handler function for the `search_postcode` tool, which searches for Swiss postcodes by city or locality name using the swisstopo API.

  case "search_postcode": {
    const cityName = String(args.city_name ?? "").trim();
    if (!cityName) {
      throw new Error("city_name must not be empty.");
    }
  
    const findUrl = buildUrl(`${BASE}/rest/services/api/MapServer/find`, {
      layer: PLZ_LAYER,
      searchText: cityName,
      searchField: "langtext",
      returnGeometry: false,
      sr: 4326,
    });
    const findData = await fetchJSON<PlzFindResponse>(findUrl);
  
    const entries = findData.results.map((r) => ({
      postcode: r.attributes.plz,
      locality: r.attributes.langtext,
      additionalNumber: r.attributes.zusziff !== "00" ? r.attributes.zusziff : undefined,
    }));
  
    // Deduplicate by PLZ (multiple records can share same PLZ with different suffixes)
    const seen = new Set<number>();
    const unique = entries.filter((e) => {
      if (seen.has(e.postcode)) return false;
      seen.add(e.postcode);
      return true;
    });
  
    return JSON.stringify({
      query: cityName,
      count: unique.length,
      results: unique,
      source: "swisstopo — Amtliches Ortschaftenverzeichnis",
    });
  }

• src/modules/post.ts:156-169 (schema)

  The schema definition for the `search_postcode` tool.

    name: "search_postcode",
    description:
      "Search Swiss postcodes by city or locality name. Returns all PLZ entries matching the name. Source: Swiss federal geodata (swisstopo).",
    inputSchema: {
      type: "object",
      required: ["city_name"],
      properties: {
        city_name: {
          type: "string",
          description: "City or locality name, e.g. \"Zürich\", \"Bern\", \"Locarno\"",
        },
      },
    },
  },