KYB Vetter

Verify Polish counterparties from inside Claude or from your own systems: VAT white list status, bank account assignment, KRS extract and a receipt that proves the check happened. Hosted MCP server and REST API over the official public registers.

Add it to Claude

1. Settings → Connectors → Add custom connector.
2. URL: https://mcp.kybvetter.dev/mcp. Claude detects the sign-in flow itself.
3. Sign in, accept the consent screen, and ask in a chat: “Verify the company with NIP 7740001454”.

Tools exposed to the model (all read-only):

Tool	What it does
verify_company	VAT status, registry name and addresses, KRS summary, warnings, receipts
check_bank_account	Whether a bank account is assigned to the NIP on the white list
verification_history	Your own past checks of a NIP

REST API

The same checks over HTTPS with an API key or an OAuth bearer token:

curl -H "X-API-Key: $KEY" https://api.kybvetter.dev/v1/companies/7740001454

Interactive schema: api.kybvetter.dev/docs.

Sources

• VAT white list (Ministry of Finance): status, accounts, registration history.
• KRS (National Court Register): company extract, representatives.
• CEIDG (sole traders): passed through, never stored.

Every answer carries a receipt (request id, timestamp, register) so you can show that the verification took place.

Documentation · Privacy policy · Contact: support@kybvetter.dev