Invoice & Payment ID Validator — remote MCP server

For accounts-payable and finance teams: before you pay an invoice, get a pay, review or hold verdict on the supplier’s bank and tax details.

1. Connect (free, no key; works in Claude Desktop, Cursor, Cline, VS Code and any client that supports remote Streamable HTTP):

{
  "mcpServers": {
    "invoice-validator": {
      "url": "https://invoice-validator.mohamed-bahaa53000.workers.dev/demo/mcp"
    }
  }
}

2. Ask: “Should I pay this Irish supplier’s invoice? VAT IE6388047V, IBAN DE89370400440532013000, EUR.” Your agent calls:

{"name":"check_invoice_payee","arguments":{"vat":"IE6388047V","iban":"DE89370400440532013000","supplier_country":"IE","currency":"EUR"}}

3. Get (real output from the free demo endpoint, trimmed):

{"verdict":"hold","risk_score":45,
 "summary":"Hold payment: Supplier is in IE but wants payment to a DE bank account: the classic changed-bank-details fraud pattern. Confirm by phone using a known number.",
 "reasons":[{"code":"iban_country_differs_from_supplier","severity":"high"}],
 "checks":{"iban":{"valid":true,"country":"DE","sepa":true},"vat":{"valid":true,"country":"IE"}}}

Both IDs are valid on their own. The mismatch between them is what triggers the hold.

What makes it different

Most IBAN/VAT APIs check each number on its own: “this IBAN is well-formed”. That misses the real invoice-fraud signal, which is a mismatch between numbers that are each valid:

• Changed bank details: your German supplier’s invoice asks for payment to a Dutch or Lithuanian account. Every ID is valid; the verdict is hold.
• BIC from a different country than the IBAN: the two don’t belong to the same account.
• VAT registered to someone else: with live=true, the VIES-registered company name is compared with the supplier name.
• Unregistered VAT, test BICs, EUR invoices paid to non-SEPA accounts.

It is also MCP-native with a free, keyless demo endpoint, so an agent can try it in one config line. Single-ID validators are included too.

No-code version

Not building an agent? The same checks come in ready-made tools:

• Free IBAN & VAT checker in your browser, with no sign-up.
• Free n8n template: AP Invoice Triage pulls Gmail PDF invoices into Google Sheets with Gemini.

Try it free

• No key, right now: point any MCP client at https://invoice-validator.mohamed-bahaa53000.workers.dev/demo/mcp (10 tool calls per IP per day).
• Free RapidAPI plan: 100 requests/month on the Basic plan, no card needed. Pro is $10 for 10,000.