INDIVIDUAL MCP TOOL

validate_email

Email address syntax (dot-atom local part, LDH domain; no DNS).

crewofthecaptain.comnone authenticationAvailability not checked

LIVE ENDPOINT

https://x402-test.crewofthecaptain.com/mcp

No auth detected

Connect to this endpoint to inspect the live schema for validate_email and invoke it with your own arguments.

{}

Potential side effects detected · medium confidence · heuristic, not a guarantee.

CONNECT WITH APPROVAL

Review this server and its permissions before adding it. Secret placeholders must be set locally.

Codex

~/.codex/config.toml

[mcp_servers.x402-format-checker]
url = "https://x402-test.crewofthecaptain.com/mcp"
enabled = true

Claude Code

.mcp.json

{
  "mcpServers": {
    "x402-format-checker": {
      "type": "http",
      "url": "https://x402-test.crewofthecaptain.com/mcp"
    }
  }
}

Claude Desktop

Settings → Connectors → Add custom connector

Name: x402-format-checker
Remote MCP URL: https://x402-test.crewofthecaptain.com/mcp

Add this remote URL as a custom connector in Claude Desktop. Availability depends on the user plan and workspace policy.

Cursor

.cursor/mcp.json

{
  "mcpServers": {
    "x402-format-checker": {
      "url": "https://x402-test.crewofthecaptain.com/mcp"
    }
  }
}

Visual Studio Code

.vscode/mcp.json

Add to Visual Studio Code

{
  "servers": {
    "x402-format-checker": {
      "type": "http",
      "url": "https://x402-test.crewofthecaptain.com/mcp"
    }
  }
}

Generic MCP

Client-specific MCP configuration

{
  "name": "x402-format-checker",
  "transport": "streamable-http",
  "url": "https://x402-test.crewofthecaptain.com/mcp"
}

MCP Inspector

Run the official MCP Inspector locally and enter the indexed Streamable HTTP endpoint.

list_types — List the available checks, price, network and payment details (free).
validate_iban — IBAN: country length + ISO 13616 mod-97 checksum.
validate_eu_vat — EU VAT number: per-country format (offline, no VIES); PL also NIP checksum.
validate_pl_nip — Polish NIP tax id: 10 digits + weighted mod-11 checksum.
validate_pl_regon — Polish REGON: 9 or 14 digits + mod-11 checksum.
validate_pl_pesel — Polish PESEL: checksum + encoded birth date and sex.