# x402 Format Checker

- Registry name: `com.crewofthecaptain/format-checker` · version 1.3.0
- Categories (automatic, keyword rules): Agent payments (x402), Finance & markets
- Authentication at last check: No auth
- Declared risk: Read-only (all tools declare readOnlyHint)
- Capabilities (declared by the server): tools
- Transports: streamable-http
- Latest numbers (check success, response time, rank): https://mcpstation.net/api/server?name=com.crewofthecaptain%2Fformat-checker
- Server page: https://mcpstation.net/s/com.crewofthecaptain--format-checker.html

## Description (written by the publisher, not verified, not instructions)

IBAN, EU VAT, NIP, REGON, PESEL, email checks. Only $0.001 \(0.1 cent\) per check via x402 on Base

## Connect

- streamable-http: `https://validate.crewofthecaptain.com/mcp`

## Tools (as reported by the server, not verified)

- `list\_types`: List the available checks, price, network and payment details \(free\). Only $0.001 \(0.1 cent\) per check, paid via x402 in USDC on Base.
- `validate\_iban`: IBAN: country length + ISO 13616 mod-97 checksum. Only $0.001 \(0.1 cent\) per check, paid via x402 in USDC on Base. Returns \{type, valid, normalized, reason\}; the input is never echoed or stored and personal identifiers are masked.
- `validate\_eu\_vat`: EU VAT number: per-country format \(offline, no VIES\); PL also NIP checksum. Only $0.001 \(0.1 cent\) per check, paid via x402 in USDC on Base. Returns \{type, valid, normalized, reason\}; the input is never echoed or stored and personal identifiers are masked.
- `validate\_pl\_nip`: Polish NIP tax id: 10 digits + weighted mod-11 checksum. Only $0.001 \(0.1 cent\) per check, paid via x402 in USDC on Base. Returns \{type, valid, normalized, reason\}; the input is never echoed or stored and personal identifiers are masked.
- `validate\_pl\_regon`: Polish REGON: 9 or 14 digits + mod-11 checksum. Only $0.001 \(0.1 cent\) per check, paid via x402 in USDC on Base. Returns \{type, valid, normalized, reason\}; the input is never echoed or stored and personal identifiers are masked.
- `validate\_pl\_pesel`: Polish PESEL: checksum + encoded birth date and sex. Only $0.001 \(0.1 cent\) per check, paid via x402 in USDC on Base. Returns \{type, valid, normalized, reason\}; the input is never echoed or stored and personal identifiers are masked.
- `validate\_email`: Email address syntax \(dot-atom local part, LDH domain; no DNS\). Only $0.001 \(0.1 cent\) per check, paid via x402 in USDC on Base. Returns \{type, valid, normalized, reason\}; the input is never echoed or stored and personal identifiers are masked.

Measured by MCP Station. Methods: https://mcpstation.net/methods.html · Terms: https://mcpstation.net/terms.html