EU VAT validation API for AI agents
Every intra-EU B2B invoice legally requires a valid VAT number - an invalid one can make the reverse-charge mechanism inapplicable and expose you to tax reassessment. This endpoint checks any EU VAT number in real time against VIES, the European Commission's official system.
Answers are minimal by design (valid / not valid + request timestamp) and GDPR-clean. Agents pay $0.005 per check in USDC - no registration, perfect for billing and compliance automations that verify at invoice time.
Endpoint
GET /v1/eu/vat-check — $0.005 per call (USDC on Base, x402). Also available as the MCP tool validate_vat_eu on https://data.greeneris.io/mcp.
Parameters
| Param | Description |
|---|---|
cc | Member state code, e.g. FR, DE, IE (also EL, XI) |
vat | VAT number without the country prefix, e.g. 6388047V |
Example
curl -i "https://data.greeneris.io/v1/eu/vat-check?cc=IE&vat=6388047V"
# HTTP/1.1 402 Payment Required + machine-readable quote
# (any x402 client pays the quote and retries automatically)Response after payment:
{"ok": true, "data": {"country_code": "IE", "vat_number": "6388047V", "is_valid": true, "request_date": "2026-07-14T09:12:03Z"}}What agents use it for
- Validate the customer's VAT number at invoice-generation time
- Batch-check supplier master data for stale or wrong VAT numbers
- Gate reverse-charge invoicing on a live VIES confirmation
How payment works
Call the endpoint: you get HTTP 402 with a signed quote (price, receiving address, network). Your agent pays a few tenths of a cent in USDC on Base (gasless, EIP-3009) and retries - one round trip, no account, no API key. Settlement only happens after a successful answer. Full catalog: llms.txt.