Japan Data APIs for AI Agents

8 production APIs covering the data an agent needs to operate in the Japanese market — payable per call with USDC via x402. No API keys. No signup. A 402 response tells your agent exactly how to pay.

日本の住所・フリガナ・鉄道遅延・国会・祝日・天気・法人番号・旅行用eSIMを、AIエージェントが x402 で従量課金のまま直接呼べる API 群です。

Quickstart — HTTP (x402)

# 1. Call any endpoint. You get HTTP 402 with payment instructions.
curl -X POST https://address.agentic-jp.com/normalize \
  -H 'Content-Type: application/json' \
  -d '{"address":"東京都渋谷区渋谷２ー２１－１"}'

# 2. Pay with any x402 client (fetch/axios wrappers, AgentKit, etc.)
#    npm: @x402/fetch, @x402/axios  —  python: x402

Quickstart — MCP (Claude, Cursor, any MCP client)

npx -y @mameta/japan-data-mcp   # 28 tools across the 7 data APIs
# set EVM_PRIVATE_KEY (wallet with USDC on Base) to enable paid calls

APIs

Address $0.001–0.005

Normalize, geocode, reverse-geocode and parse Japanese addresses. Postal-code lookup. Confidence scores.

manifest

Furigana $0.001–0.005

Kanji → furigana/romaji, name readings with candidates, text normalization, name-type classification.

manifest

Transit $0.001–0.015

Real-time train delays (ODPT), line disruptions, route planning and delay-aware alternative routes for Tokyo rail.

manifest

Diet (Parliament) $0.005–0.01+

National Diet members and full-text minutes search (official National Diet Library archive).

manifest

Holiday $0.001–0.005

Japanese public holidays 1955–2027, business-day math (add / next / count) skipping weekends and holidays.

manifest

Weather $0.001–0.005

JMA (気象庁) forecasts, warnings/advisories and overviews for all 58 forecast offices, 341 area aliases.

manifest

Corporate Registry $0.001–0.25

All 5.78M Japanese corporations from the National Tax Agency registry: lookup, fuzzy name search, KYB verify, and a one-call $0.25 KYB report (status, readings, risk flags). Also on Apify: single lookup · bulk enrichment.

manifest

Travel Connectivity $0.05

Japan eSIM concierge: trip length + usage profile in, best-value eSIM plan out — with ready-to-execute x402 purchase instructions (Cryptorefills catalog).

manifest

Payment details

Every endpoint declares full input/output JSON Schema and examples in its 402 accepts extension and /.well-known/x402 manifest, so agents can integrate without human docs.

Why these APIs

Japanese addresses, name readings, and corporate identifiers are notoriously hard to handle from outside Japan — fullwidth/halfwidth variants, old-form kanji, multiple valid name readings, a registry published only as CSV dumps. These APIs wrap the authoritative public sources (日本郵便, 気象庁, 国税庁, 内閣府, ODPT, 国会会議録) behind clean JSON with confidence scores, built for machine consumption.