REGON (Polish business register)

Name: REGON (Polish business register)
Author: SmartMobileHouse

by SmartMobileHouseversion 0.2.3i★ –iRuns on your computer

Registry nameio.github.SmartMobileHouse/regon-mcp

Install

Overview

Description from the maker (original English)

Look up Polish businesses in the GUS REGON register (BIR1) by NIP, REGON, or KRS.

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: REGON_API_KEY

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: REGON_API_KEY, REGON_ENV

Values marked secret are keys to your account. Never share them or paste them into a chat.

You need

PyPIPython’s uv installed (for the uvx command)

Which app do you use?

ClaudeClaude CodeCursorVS CodeChatGPT

Pick your app above. We remember it, so next time the button says “Install in …”.

Open Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json

{
  "mcpServers": {
    "regon": {
      "command": "uvx",
      "args": [
        "regon-mcp"
      ],
      "env": {
        "REGON_API_KEY": "your-value",
        "REGON_ENV": "your-value"
      }
    }
  }
}

Run this in your terminal

claude mcp add regon --env REGON_API_KEY=your-value --env REGON_ENV=your-value -- uvx regon-mcp

Fill in the empty values before running it.

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "regon": {
      "command": "uvx",
      "args": [
        "regon-mcp"
      ],
      "env": {
        "REGON_API_KEY": "your-value",
        "REGON_ENV": "your-value"
      }
    }
  }
}

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.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "regon": {
      "type": "stdio",
      "command": "uvx",
      "args": [
        "regon-mcp"
      ],
      "env": {
        "REGON_API_KEY": "your-value",
        "REGON_ENV": "your-value"
      }
    }
  }
}

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

REGON_API_KEY secret env
GUS BIR USER_KEY for live production data. Omit to use the public test key against the anonymized test database.
REGON_ENV env
Which GUS environment to query: 'test' (default) or 'prod'. Use 'prod' with a real USER_KEY.

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 SmartMobileHouse, 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 32744 servers in this category
Published to the registry more recently than 92% of the other 32744 servers in this category
Basic checks equal to or better than 100% of the other 32744 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 REGON (Polish business register) 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: REGON_API_KEY

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 (0.2.3) reached the registry 3 days ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need Python (uv) on your computer.

What can I use instead?

In the same category: Spec Driven Development, Remote Desktop Commander, Date Math

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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.

regon-mcp

A Model Context Protocol server that gives AI assistants clean, typed access to the Polish REGON business register (GUS BIR1). Look up any Polish company by NIP, REGON, or KRS and get back structured data — name, address, legal form, activity codes — without touching the underlying SOAP API.

The official GUS BIR1 API is a WCF SOAP service with WS-Addressing, MTOM multipart responses, an HTTP-header session token, and XML-nested-inside-XML result payloads. regon-mcp hides all of that behind a handful of simple tools.

Built and maintained by Smart Mobile House —

secure AI implementation for enterprise.

Background and design notes: the regon-mcp write-up.

Tools

Tool	Description
`search_by_nip(nip)`	Look up an entity by 10-digit NIP (tax id).
`search_by_regon(regon)`	Look up an entity by 9- or 14-digit REGON.
`search_by_krs(krs)`	Look up an entity by 10-digit KRS (court register).
`search_bulk(identifiers, id_type)`	Look up up to 20 entities of one type at once.
`get_full_report(regon, report_type)`	Fetch a detailed report for one entity.
`list_report_types()`	List valid report names, with guidance on which to use.

Every response includes a source block that names the register (REGON / GUS), the environment, and a UTC retrieved_at timestamp — so downstream use can cite the data correctly, as GUS requires.

Quick start

No install needed — run it straight from the repo with uv:

uvx --from git+https://github.com/SmartMobileHouse/regon-mcp regon-mcp

By default it uses the public test key against the anonymized GUS test database, so it runs with zero setup. For live data, request a free USER_KEY from regon_bir@stat.gov.pl and set the environment variables below.

Use it in Claude Desktop / Claude Code

Add to your MCP config (e.g. claude_desktop_config.json or a project .mcp.json):

"mcpServers": { "regon": { "command": "uvx", "args": ["--from", "git+https://github.com/SmartMobileHouse/regon-mcp", "regon-mcp"], "env": { "REGON_API_KEY": "your-user-key", "REGON_ENV": "prod" } } } }

During development, point it at a local checkout instead:

"mcpServers": { "regon": { "command": "uvx", "args": ["--from", "/absolute/path/to/regon-mcp", "regon-mcp"], "env": { "REGON_API_KEY": "abcde12345abcde12345" } } } }

Configuration

Variable	Default	Description
`REGON_API_KEY`	public test key	Your GUS BIR `USER_KEY`.
`REGON_ENV`	`test`	`test` (anonymized data) or `prod` (live data).
`REGON_TIMEOUT`	`30`	HTTP timeout in seconds.

Use REGON_ENV=prod only with a real USER_KEY; the test key works only against the test environment.

Development

git clone https://github.com/SmartMobileHouse/regon-mcp

cd regon-mcp uv sync # create the venv and install deps uv run pytest # offline tests: validation, parsing, mocked client,

and an in-memory MCP tool-discovery smoke test.

(network tests are deselected by default)

uv run regon-mcp # run the server over stdio

Live tests against the GUS endpoint (deselected unless opted in):

REGON_RUN_NETWORK=1 uv run pytest -m network # session lifecycle (test env) REGON_PROD_KEY= uv run pytest -m network # positive-control on live data

The client is a small hand-rolled SOAP layer over httpx (see src/regon_mcp/client.py) — no heavyweight SOAP stack, no runtime WSDL fetch.

Notes & limitations

The GUS test database is anonymized and returns little or no entity data. Meaningful results require a production USER_KEY with REGON_ENV=prod.
Respect the GUS terms of use and rate limits. This project is an independent open-source client and is not affiliated with or endorsed by GUS.
Data belongs to GUS. When you present it, cite REGON / GUS with the retrieval date (surfaced in every response's source block).

REGON (Polish business register)

Overview

PopNx MCP’s three pillars

What you can do with it

Install

Before you install

Values you fill in

What it can do

Basic checksi

Maker matches the repo

Still maintained

Has a licence

Endpoint responds

Sign-in with OAuth

No hidden instructions in tool descriptions

Compared with others in Otheri

Common questions

Alternatives

Spec Driven Development

Remote Desktop Commander

Date Math

README from the maker

regon-mcp

Tools

Quick start

Use it in Claude Desktop / Claude Code

Configuration

Development

and an in-memory MCP tool-discovery smoke test.

(network tests are deselected by default)

Live tests against the GUS endpoint (deselected unless opted in):

Notes & limitations

License