Japan Corporate Number MCP server

@pipeworx/japan-corporate-number

Japan's National Tax Agency (国税庁) corporate-number register (法人番号公表サイト) — the complete spine of every 13-digit 法人番号 issued since 2015-10-05: legal name, katakana reading and English name when NTA holds one, address, corporate kind (stock company, LLC, government body, NPO, etc.) and status (active, or closed/merged with the narrative NTA published). 5,837,980 entities as of the 2026-09-30 cut.

Part of Pipeworx — an MCP gateway connecting AI agents to 1769+ live data sources. This is an independent, unofficial integration — not affiliated with, endorsed by, or published by the upstream provider.

gBizINFO (mcps/gbizinfo, METI) is a different source hanging richer government records — procurement, subsidies, patents, financials — off the same corporate number, with partial coverage. This pack is the complete spine (every registered number, from NTA directly); use gbizinfo for the government-record detail once you have a number.

Tools

Validates the check digit before looking up (see "Check digit" below) and returns found: false with a reason for a malformed number, a check-digit failure, or a correctly-formed number simply not in the register — never an empty object.

• jpcorporatenumber(number) — look up one entity by its 13-digit 法人番号.

(substring, corporate-suffix-insensitive) or, for the subset of entities NTA published one for, an English name/katakana reading. prefecture accepts a Japanese name, an English name, or a 2-digit code.

• jpcompanysearch(name, prefecture?, limit?) — search by Japanese name

Auth

Keyless. The gateway supplies the data directly — no caller-facing key, and no vendor key of any kind (the register is published as a monthly file, not a live API). The tools work only through the hosted gateway: a standalone build has no data to read and returns a loud error (StoreUnavailableError) naming that, never an empty result.

Data source & reuse terms

(法人番号公表サイト) — the whole-country corporate-number register, published monthly. Pipeworx loads each monthly edition; dataasof on every response is when the loaded edition was taken. The fetch mechanics (and the verified column mapping) live only in scripts/japan-corporate-number/README.md, which does not publish — CLAUDE.md step 9b (a4c024647): name the source, never the source file/path/form fields.

• Japan National Tax Agency (国税庁), Corporate Number Publication Site

terms-of-use page): attribution is required ("本コンテンツを利用する際は出典を記載してください" — when using this content, state the source); edits/derivative processing must be disclosed separately from the attribution; and edited/processed data must never be presented as though the government itself produced it ("編集・加工等した情報を、あたかも国（又は府省等）が作成したかのような 態様で公表・利用することは禁止します"). Otherwise permissive — commercial reuse and redistribution are not restricted. This README and every tool response carry the source and dataasof; the data is NTA's, reformatted by Pipeworx, never presented as government-produced.

• Terms of use (Japan's Public Data License v1.0, quoted from NTA's

Kind codes (法人種別)

The complete set observed: 101 national government organization, 201 local government, 301 Kabushiki Kaisha (stock company), 302 Godo Kaisha (LLC-equivalent), 303 Gomei Kaisha, 304 Goshi Kaisha, 305 other registered corporation (e.g. incorporated association/foundation), 399 other, 499 foreign company etc. Labels are best-effort English glosses of NTA's standard code table; the raw code is always returned alongside the label.

Status — a real correctness trap (and a second one inside it)

Shortened. The full README is on GitHub.