Japan Law Search

io.github.easakuraPublished by GitHub account easakurav1.0.0Updated Oct 24, 2026

Full-text search of all current Japanese laws (official e-Gov data), down to exact article text.

VerifiedStreamable HTTPWeb executableWeb Search & ScrapingKnowledge & Memory

Overview

AI-generated overview

A hosted MCP server that lets an assistant full-text search current Japanese laws from official e-Gov data and retrieve exact article text.

What you can do
Search all current Japanese laws by body text or title, with matched snippets, categories, promulgation dates and official links. Browse a law's table of contents, with long statutes compressed to chapter level. Fetch the exact text of a specific article, accepting flexible references such as numerals or kanji forms and normalizing them. Output is formatted as clean plain text with paragraph and item numbering preserved.
When to use it
Useful for legal-tech, compliance, HR and contract-review work involving Japanese statutes, where an assistant needs to find the relevant law and quote the exact article rather than rely on memory.
Requirements
A remote MCP endpoint; no local package, account, API key or header is declared. The server fetches live from the official e-Gov Laws API on each call, so network access is needed. Usage is billed per tool call through the hosting store.
Before you install
Pay per tool call (stated as $0.02 per search, table of contents or article retrieval), so frequent use incurs costs. Queries and retrieved law content pass through the hosted service and the upstream e-Gov API. Results reflect the currently enforced revision fetched live, so verify citations before relying on them.

Installation

In SourceWeft

  1. Open Japan Law Search in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.

Use with an agent

Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.

Read https://sourceweft.com/mcp/io.github.easakura%2Fjapan-law-search-mcp/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.

Read the install guide the agent follows

Other MCP clients

Add this to your client's mcpServers config.

{
  "mcpServers": {
    "japan-law-search": {
      "type": "http",
      "url": "https://horei-mcp.easakura.workers.dev/mcp"
    }
  }
}

README

Japan Law Search MCP — 日本の法令検索

Give your AI agent authoritative access to all ~10,000 Japanese laws and regulations.

This MCP server searches and retrieves the full text of current Japanese legislation — acts, cabinet orders, and ministerial ordinances — from the official e-Gov Laws API (Government of Japan). Built for legal-tech, compliance, HR, and contract-review AI agents working with Japanese law.

Why this server?

Japanese statutes are published as deeply nested XML with kanji numerals, era-based dates, and no convenient full-text API surface for LLMs. This server turns that into three clean, token-efficient tools.

Tools

search_laws

Full-text search across the body text of every current law (or search by law title). Returns matched snippets, law categories, promulgation dates, and official links.

get_law_structure

Table of contents for any law: chapters, sections, and article headings. Long statutes (e.g. the Civil Code with 1,000+ articles) are automatically compressed to chapter level to save tokens.

get_law_article

Retrieve the exact text of any article. Accepts flexible references — 3, 第3条, 第三条の二, 3の2 — and normalizes kanji numerals automatically. Output preserves paragraph and item numbering as clean plain text.

Example queries your agent can now answer

  • 「電子署名法で電子署名が有効とされる条件は？」→ finds Article 3 and quotes it verbatim
  • "What does the Labor Standards Act say about overtime limits? Quote the exact article."
  • 「個人情報保護法の目次を見せて、第三者提供に関する条文を特定して」

Data source & freshness

Official e-Gov Laws API v2 (Government of Japan), fetched live on every call — always the currently enforced revision, including amendments enforced this month.

Pricing

Pay per tool call. One search, one table of contents, or one article retrieval = one event. No subscription, no minimum.

日本語

日本の現行法令（約1万件）を全文検索し、条文を取得できるMCPサーバーです。巨大な法令XMLをAIが読みやすいテキストに整形し、「第三条の二」等の表記ゆらぎも自動吸収します。リーガルテック・コンプライアンス・労務系AIに最適です。

Get started

This is a hosted (remote) MCP server, available on Apify Store:

👉 https://apify.com/e-asakura/japan-law-search-mcp

The store page includes setup instructions for Claude, ChatGPT, Cursor, and any MCP-compatible client. Pay-as-you-go: $0.02 per tool call, no subscription.

Built by Edward Asakura — Japanese data infrastructure for AI agents. Part of the SEKISHO series: subsidies / laws / parliament.

Source: README.md at commit c3ac381

Tools

0
SourceWeft has not read this server's tools yet.

Version history

1
  1. v1.0.0LatestSep 16, 2026

Score

85% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 daysRequired25 pts
  • Auth declaredRequired10 pts
  • Tools listedRequired15 pts

    Answer tools/list without a credential, or ship a package that starts in a sandbox without one.

  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts