Claude · Anthropic
Japanese law in Claude
Claude can read Japanese law from this site as it answers: it searches the statutes, opens the article, quotes the Japanese with the Ministry of Justice's English where there is one, and gives you the link to check it. You add it once as a custom connector, and it is there in the web app, the desktop app, Cowork and on your phone.
Set it up
- 1
Open claude.ai and go to Customize, then Connectors — or use the Add to Claude button above, which opens that dialog with everything filled in.
- 2
Choose Add custom connector. Name it japanlaw.org and paste the server's URL:
Remote MCP server URLhttps://japanlaw.org/mcp - 3
Leave the authentication settings empty — the server needs no sign-in — and add it.
- 4
In a chat, open the tools menu under the message box and make sure japanlaw.org is switched on. Then ask about a Japanese law.
Before you start
- On a personal plan you add it yourself; the free plan allows one custom connector.
- On a Team or Enterprise plan an Owner adds it for the organization (Organization settings, Connectors), and each member then turns it on.
- Claude calls the server from Anthropic's systems, so it works the same on every device once added.
Then ask
- Under Japanese law, how many hours of overtime can my employer ask of me in a month? Quote the article.
- What does Article 36 of the Labor Standards Act say? Show the Japanese and say whose English it is.
- I'm renting an apartment in Tokyo. When can the landlord refuse to renew the lease?
What Claude can do with it
search- Finds provisions, laws and defined terms by Japanese or English words, in every law held or in one, best match first. Each result has an id for fetch and the page's URL.
fetch- Reads what a search result's id names: a provision in Japanese with its English, each line marked as the Ministry's translation or machine translation — in force, or as it stood on a day; or a law's overview and outline.
list_laws- Every law japanlaw.org holds: title, number, kind, date of the text in force and how much of it has English.
get_law- One law: what it is for, who it binds and who it does not — its exceptions and how it is enforced on request — the texts of it held, earlier and to come, and its chapters, or what is under one of them.
get_provision- An article, paragraph or item by its citation — 第三十六条第二項, Article 36(2) or art-36/par-2 — in Japanese and English, with what it cites, the terms it defines and its URLs: in force, or as it stood on a day. Shown as a card where the app can draw one.
get_citing_provisions- Every provision in the collection that cites the one given, with links. No official source publishes this direction.
get_definitions- The words a law defines for itself — 労働者, 賃金 — each with the statute's own definition, its English and whose that is, a plain explanation, where it is defined and how far it reaches. Given a provision, the definitions that apply in it and the legal vocabulary it uses.
get_amendments- A law's amendments: the amending Act, its number, the day it takes effect and whether it is in force. Given one, every provision it changes, before and after, in Japanese and English, each English marked as the Ministry's or machine translation.
Two rules that keep the answer honest
Carry the attribution through
Every English paragraph is marked as the Ministry of Justice's translation or as this site's machine translation. Passing the second off as the first is the most damaging thing an answer built on this data can do. Keep the distinction in what you hand back.
Point back to the official original
Only the Japanese text as published by the government has legal effect; every English rendering, the Ministry of Justice's included, is a reference. Include the provision's link so the reader can check the original before acting, and do not present any of it as legal advice.
