mcp-polish-data

MCP Server with Polish public data — KRS, CEIDG, GUS BDL for Claude, Cursor, and Windsurf.

What is it

A Model Context Protocol (MCP) server that gives AI assistants direct access to Polish government registries and GUS statistics without leaving the chat. Install once, and Claude or Cursor automatically knows how to look up companies in KRS, verify sole traders in CEIDG, and retrieve regional statistics from GUS BDL.

MIT licensed, no API key required.

Related MCP server: Countries MCP Server

Features

• KRS — look up a company by NIP (via VAT Whitelist — KRS API doesn't support name search), retrieve full extract by 9 or 10-digit KRS number

• CEIDG — search sole trader businesses by name, NIP, REGON, or owner surname

• GUS BDL — population by voivodeship, unemployment rate, average gross salary, statistical variable discovery

• VAT Whitelist (Biala Lista MF) — verify taxpayer VAT status (active/exempt/deregistered), registered bank accounts, SHA-256 response hash for audit trail

• NIP / REGON / PESEL validation — checksum verification with no API calls; PESEL also extracts date of birth and gender (flagged PII-sensitive)

• SQLite caching — transparent response cache with per-tool TTL (KRS/CEIDG: 7 days, GUS: 30 days, VAT: 1 day); validation tools are never cached

• Retry with exponential backoff — handles 429 (respects Retry-After header) and 5xx errors with up to 3 attempts and jitter

• Graceful degradation — when CEIDG requires a JWT token, the server provides a helpful message instead of crashing

• Zero configuration — single pip install, no API keys required for basic functions

• Python 3.11+ — async/await, httpx, FastMCP 2.0

Stack

Getting Started

pip install mcp-polish-data

Claude Desktop

Edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "polish-data": {
      "command": "mcp-polish-data"
    }
  }
}

Restart Claude Desktop — tools will appear automatically.

Cursor / Windsurf

git clone https://github.com/emilpinski/mcp-polish-data
cd mcp-polish-data
pip install -e ".[dev]"
pytest tests/ -v -m "not integration"

Available Tools

Environment Variables

Example Prompts

• "Look up NIP 5270103391 and tell me the company name and address"

• "Compare the unemployment rate in 2023 across all voivodeships"

• "What is the average salary in Pomerania vs Masovia?"

• "Find all CEIDG sole traders with surname Kowalski in Kraków"

Status

Live — mcp-polish-data.vercel.app | PyPI: mcp-polish-data

Built by Emil Piński

Screenshots