Spec Driven Development
by formulahendry
MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.
Runs on your computer★ 440MITUpdated 14 months ago
Install
JP Data (Japanese Public Business Data)
Overview
Description from the maker (original English)
Japanese open-data MCP server: corporate-number validation, zengin bank codes, national holidays
PopNx MCP’s three pillars
These three are never merged into one score: opinions, measurements and popularity are different things.
- User voiceiNo reviews yetReviews open together with accounts in a later step
- Our basic checksi1 of 1 passedChecked from public information; code not scanned yet
- UsageiNot measured yet★ –
What you can do with it
We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.
- Connection: Runs on your computer
- Transport: stdio
- Category: Other
- You need to fill in: NTA_APP_ID
Install
Pick the AI app you use, then copy the settings.
Before you install
- Basic checks: 1 of 1 passed
- Runs on your computer with your user’s permissions (files, network, apps).
- You fill in yourself:
NTA_APP_ID
Values marked secret are keys to your account. Never share them or paste them into a chat.
Which app do you use?
Pick your app above. We remember it, so next time the button says “Install in …”.
Download the maker’s .mcpb file
The link goes to the maker’s own file; we do not host or repackage it. Open the file and Claude Desktop installs it.
Run this in your terminal
Fill in the empty values before running it.
Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
This one runs on your computer, and ChatGPT can only connect to servers on the internet. Pick another app.
Your choice stays on this device in a cookie; no account needed.
Values you fill in
- Optional free NTA Web-API application ID for live corporate-registry data; without it, corporate lookups use a bundled synthetic sample set tagged SYNTHETIC_SAMPLE.
These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.
What it can do
Runs on your computer; the tool list appears in your AI app after you install it.
Basic checksi
We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 7, 2026
- ✓ Pass
Maker matches the repo
The registry name was verified with the GitHub account kimotostudio, which owns the repo
- … Not checked yet
Still maintained
We have not read this repo from GitHub yet
- … Not checked yet
Has a licence
We have not read this repo from GitHub yet
- – Not applicable
Endpoint responds
This one runs on your computer; there is no internet endpoint
- – Not applicable
Sign-in with OAuth
Runs on your computer and uses local settings instead
- … Not checked yet
No hidden instructions in tool descriptions
Runs on your computer; we can only read tool lists from internet endpoints
Compared with others in Otheri
- More stars than 0% of the other 18329 servers in this category
- Published to the registry more recently than 19% of the other 18329 servers in this category
- Basic checks equal to or better than 100% of the other 18329 servers in this category
Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.
Common questions
Is JP Data (Japanese Public Business Data) safe?
It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.
What keys or codes does it need?
You need to fill in: NTA_APP_ID
Does it run on my computer or in the cloud?
It runs on your computer. Your AI app starts it when needed, and data does not pass through the maker’s servers (unless it calls an online service itself).
Is it still maintained?
The GitHub repo last changed –, and the latest version (0.1.0) reached the registry 3 months ago.
Which apps can use it?
Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need MCPB on your computer.
What can I use instead?
In the same category: Spec Driven Development, Remote Desktop Commander, Excaliself
Alternatives
Servers in the same category from other makers, sorted by stars.
Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi
Remote Desktop Commander
by desktop-commander
Remote Desktop Commander: use files, terminal and processes on your own computers from any AI app.
Runs in the cloud★ 211Updated 2 days ago
Install
Excaliself
by maciekzygmunt
Find, read, create, edit, and organize Excalidraw drawings in your self-hosted Excaliself instance.
Runs in the cloudUpdated today
Install
README from the maker
Open the README
Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.
jp-data-mcp — Japanese Public Business Data for AI Agents
A free, open-source MCP server that gives AI agents the Japanese business-data primitives they most often need:
- Corporate numbers (法人番号) — offline check-digit validation and, with a (free) NTA application ID, live registry enrichment from the National Tax Agency 法人番号 Web-API: registered name, address, entity kind, dates.
- Zengin bank / branch codes (統一金融機関コード・支店コード) — the codes that describe a Japanese domestic bank transfer, with kana / hiragana / romaji.
- Japanese national holidays — official Cabinet Office holiday data, bundled.
It runs entirely on your machine. No account, no API key of ours, no payments, no telemetry — usage is not logged or reported anywhere.
Tools
| Tool | What it does |
|---|---|
validate_corporate_number | Offline format + official NTA check-digit validation of a 13-digit 法人番号 (full-width input tolerated). Does not confirm the company exists. |
lookup_corporate_number | Registry enrichment for a corporate number (live NTA Web-API when NTA_APP_ID is set; otherwise a clearly-tagged synthetic fallback — see below). |
search_corporations_by_name | Search corporations by (partial) name (live NTA Web-API when NTA_APP_ID is set). |
lookup_bank | Bank by 4-digit zengin bank code → name / kana / hiragana / romaji. |
search_banks | Search banks by name fragment (kanji / kana / hiragana / romaji). |
lookup_branch | Branch by bank code + 3-digit branch code (branch data lazily fetched from the public zengin-code dataset and cached locally). |
japan_holidays | All Japanese national holidays for a given year. |
is_japan_holiday | Whether a YYYY-MM-DD date is a national holiday. |
Important: the SYNTHETIC_SAMPLE fallback
Live corporate-registry data requires a free NTA Web-API application ID (register at the 国税庁 法人番号システム Web-API site), supplied via the NTA_APP_ID environment variable.
Without `NTA_APP_ID`, lookup_corporate_number and search_corporations_by_name fall back to a tiny bundled synthetic sample set. These records are fabricated for testing, do not correspond to real companies, and every one of them is tagged "source": "SYNTHETIC_SAMPLE" plus an explanatory note in the response — they can never be mistaken for real registry data. Check-digit validation and the bank/holiday tools do not need any key and always use real data.
Known limitation: the NTA v4 CSV column mapping is written from the published spec but has not yet been verified against a live API response. If you find a misaligned field, please open an issue.
Install & run
Requires Python 3.11+.
git clone https://github.com/kimotostudio/jp-data-mcp.gitcd jp-data-mcp pip install fastmcp httpx # or: uv sync python src/server.py # stdio MCP server
Or with uv, no explicit install step:
uv run --directory /path/to/jp-data-mcp src/server.pyClaude Desktop / MCP client config (stdio)
{"mcpServers": { "jp-data": { "command": "uv", "args": ["run", "--directory", "/path/to/jp-data-mcp", "src/server.py"], "env": { "NTA_APP_ID": "your-nta-app-id (optional)" } } } }
An .mcpb bundle (usable with MCPB-aware clients) is attached to each GitHub release.
Local HTTP mode (optional)
python src/server.py --http # streamable-http on 127.0.0.1:8765 (localhost only)Test
python test_client.pyData sources & licenses
| Data | Source | Terms |
|---|---|---|
| Corporate registry | 国税庁 法人番号システム Web-API v4 (live, only when you configure your own NTA_APP_ID) | NTA Web-API terms of use apply to your usage |
| Check-digit formula | Official NTA specification (implemented offline) | — |
| Bank / branch codes | zengin-code/source-data (bank list bundled; branch files fetched on demand) | MIT License |
| National holidays | 内閣府 国民の祝日 CSV (bundled, converted to UTF-8) | Japanese government open data |
| Synthetic corporate samples | Generated for this project (valid check digits, fictional companies) | MIT (part of this repo) |
Disclaimer
This project is not affiliated with or endorsed by the National Tax Agency, the Japanese Bankers Association, the zengin-code project, or the Cabinet Office. Data is provided as-is with no warranty of accuracy or completeness — verify against official sources before relying on it for legal, tax, accounting, or payment decisions. Bundled datasets are snapshots and may lag the official sources.
License
MIT
Local review
See the local tool walkthrough for a synthetic example and test scope.