get_metadata

Instructions

Implementation Reference

• src/index.ts:110-113 (handler)

  Request handler for the 'get_metadata' tool. Calls client.getMeta() on the JpzipClient and returns the dataset metadata (version, timestamp, entry counts) or an error if unavailable.

  case 'get_metadata': {
    const meta = await client.getMeta();
    return toolResult(meta ?? { error: 'meta.json is not available from the CDN.' });
  }

• src/index.ts:75-83 (schema)

  Tool schema definition for 'get_metadata'. Describes the tool and declares an empty input schema (no arguments required).

  {
    name: 'get_metadata',
    description:
      'Return the jpzip dataset metadata: data version (YYYY-MM), generated timestamp, total entry count, and per-prefecture counts. Useful for confirming the dataset is current.',
    inputSchema: {
      type: 'object',
      properties: {},
    },
  },

• src/index.ts:23-84 (registration)

  Tool registration: 'get_metadata' is listed in the TOOLS array and exposed to clients via the ListToolsRequestSchema handler.

  const TOOLS = [
    {
      name: 'lookup_zipcode',
      description:
        'Look up the Japanese address for a 7-digit postal code (郵便番号). Returns prefecture, city, and town(s) in kanji, katakana, and romaji, plus the JIS prefecture code and Soumu city code. Hyphens in the input are allowed.',
      inputSchema: {
        type: 'object',
        properties: {
          zipcode: {
            type: 'string',
            description: '7-digit postal code, e.g. "2310017" or "231-0017".',
          },
        },
        required: ['zipcode'],
      },
    },
    {
      name: 'search_by_address',
      description:
        'Search for postal codes by free-text address query. Matches against prefecture, city, and town in kanji, katakana, or romaji (case-insensitive substring match, whitespace ignored). First call in a session downloads the full dataset (~25MB) into memory; subsequent calls within the same session are instant.',
      inputSchema: {
        type: 'object',
        properties: {
          query: {
            type: 'string',
            description: 'Address keyword, e.g. "横浜市中区本町" / "ヨコハマシナカクホンチョウ".',
          },
          limit: {
            type: 'integer',
            description: 'Maximum number of hits to return (default 20).',
            minimum: 1,
            maximum: 200,
          },
        },
        required: ['query'],
      },
    },
    {
      name: 'list_cities_in_prefecture',
      description:
        'List all municipalities (city / ward / town / village) in a Japanese prefecture, with their Soumu city codes. Prefecture name accepts kanji, katakana, or romaji. Shares the same in-memory dataset as search_by_address.',
      inputSchema: {
        type: 'object',
        properties: {
          prefecture: {
            type: 'string',
            description: 'Prefecture name, e.g. "神奈川県" / "カナガワケン" / "Kanagawa".',
          },
        },
        required: ['prefecture'],
      },
    },
    {
      name: 'get_metadata',
      description:
        'Return the jpzip dataset metadata: data version (YYYY-MM), generated timestamp, total entry count, and per-prefecture counts. Useful for confirming the dataset is current.',
      inputSchema: {
        type: 'object',
        properties: {},
      },
    },
  ] as const;