Japanese law in OpenAI Codex

Set it up

1. 1

   Install the plugin, which brings the server and the skill together:

   terminalCopy

   codex plugin marketplace add japanlaw/plugin
   codex plugin add japanlaw@japanlaw

2. 2

   Or add only the server, without the skill, with one command:

   terminalCopy

   codex mcp add japanlaw --url https://japanlaw.org/mcp

3. 3

   Or write it into ~/.codex/config.toml yourself:

   ~/.codex/config.tomlCopy

   [mcp_servers.japanlaw]
   url = "https://japanlaw.org/mcp"

Before you start

• The same config is read by Codex in the terminal and in the IDE extension.

Then ask

• Use the japanlaw tools to check that every statute citation in this contract template points at a provision that exists in the text in force.
• Search japanlaw for 個人情報 and list the defined terms it returns, with the article that defines each.
• Fetch labor-standards-act/art-32 and write a unit test fixture from its Japanese and English.

What Codex 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

Other assistants

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