"Knip" matching MCP tools:

• nip_validateA

  PESEL/NIP/REGON ValidatorA

  Validates the checksum of a 10-digit Polish tax identification number (NIP). Checksum uses weights 6 5 7 2 3 4 5 6 7 over the first 9 digits; sum mod 11 must equal the 10th digit. A sum mod 11 of 10 is itself invalid.

  ConnectorNo auth

• pesel_validateA

  PESEL/NIP/REGON ValidatorA

  Validates the checksum of an 11-digit Polish national identification number (PESEL). Checksum uses weights 1 3 7 9 1 3 7 9 1 3 over the first 10 digits; control digit is (10 - sum mod 10) mod 10. On success also decodes the date of birth and sex embedded in the number; a checksum-valid number with an impossible calendar date (e.g. Feb 30) is still reported invalid.

  ConnectorNo auth

• regon_validateA

  PESEL/NIP/REGON ValidatorA

  Validates the checksum of a 9- or 14-digit Polish business registry number (REGON). 9-digit: weights 8 9 2 3 4 5 6 7 over the first 8 digits, sum mod 11 (10 mapped to 0) must equal the 9th digit. 14-digit: the first 9 digits must themselves be a valid 9-digit REGON, and weights 2 4 8 5 0 9 7 3 6 1 2 4 8 over the first 13 digits (sum mod 11, 10 mapped to 0) must equal the 14th digit.

  ConnectorNo auth

• kip-kgD

  Kips to kilograms, number discardedC

  Kips to kilograms, number discarded

  ConnectorNo auth