Discover and list available dataset IDs, titles, record counts, and coverage years across all 155 official Japanese datasets in Japan Official Data Megabank (demographics, real_estate, procurement, companies, medical, renewable_energy, grid_capacity, etc.). WHEN TO USE: Call this tool first when you do not know the exact 'dataset_id' to query. NEXT STEP: Pass a discovered 'dataset_id' to 'describe_japan_dataset' to inspect columns, or directly to 'search_japan_official_data' to fetch rows. WHEN NOT TO USE: Do not use this tool to fetch actual data rows (use 'search_japan_official_data' instead) or B2B bulk product bundles (use 'list_flagship_b2b_bundles').

Retrieve the exact column schema, data types, historical coverage range, primary government ministry source, and a representative sample record (including English 'prefecture_en' and 'city_en') for a single dataset. WHEN TO USE: Call this after 'list_japan_datasets' and before 'execute_japan_megabank_sql' or 'search_japan_official_data' to verify exact column names and data formats. WHEN NOT TO USE: Do not use this to search or filter multiple records (use 'search_japan_official_data' for filtered rows or 'execute_japan_megabank_sql' for aggregations).

Fetch and filter actual data records from a single dataset using standardized parameters (prefecture name, 5-digit JIS municipality code, 13-digit corporate number, or free-text keyword). Multiple filters are combined using logical AND. WHEN TO USE: Use for fast, single-table record lookups and filtered sampling once you know the 'dataset_id'. WHEN NOT TO USE: Do not use for discovering dataset IDs (use 'list_japan_datasets'), inspecting column schemas (use 'describe_japan_dataset'), or performing cross-table JOINs and GROUP BY aggregations (use 'execute_japan_megabank_sql').

Execute a read-only DuckDB SQL SELECT query across all 155 mounted datasets (10.16M+ records). Enables complex aggregations (COUNT, SUM, AVG, GROUP BY) and multi-table JOINs using 'municipality_code' (5-digit JIS code) or 'corporate_number' (13-digit ID). Enforces AST validation (single SELECT only, max 10,000 rows). PREREQUISITE: Requires a MEGA tier subscription on RapidAPI or local database access; always call 'describe_japan_dataset' first to confirm table and column names. WHEN NOT TO USE: Do not use for simple single-table keyword or prefecture lookups (use 'search_japan_official_data' instead, which works on all tiers including BASIC) or for browsing available tables (use 'list_japan_datasets').

List the 5 Flagship Enterprise All-in-One Data Bundles (BUNDLE-01 Real Estate, BUNDLE-02 Government Procurement, BUNDLE-03 Healthcare, BUNDLE-04 Renewable Energy/GX, BUNDLE-05 Municipal Finance/Resilience) with included dataset counts, total records, JPY pricing, discount rates, and qualified B2B invoice availability. WHEN TO USE: Use only when the user asks about bulk downloadable ZIP packages, enterprise pricing, or B2B invoice options. WHEN NOT TO USE: Do not use for listing individual API datasets (use 'list_japan_datasets') or querying actual data records (use 'search_japan_official_data').