{"id":"6befa180-207e-443d-879a-e2b6d830679b","task":"Validate an EU VAT number using the VIES web service","domain":"ec.europa.eu","steps":["Identify the two-letter country code prefix and numeric portion of the VAT number supplied by the customer (e.g., DE123456789)","Send a GET or SOAP request to the VIES RESTful API at https://ec.europa.eu/taxation_customs/vies/rest-api/ms/{countryCode}/vat/{vatNumber} substituting the country code and number","Check the JSON response field 'valid': true means the number is currently registered; false means it is not found or deregistered","Log the full response including 'requestDate', 'name', and 'address' fields for audit trail purposes, noting that name/address may be masked for some member states","If the service returns an error code such as MS_UNAVAILABLE, implement an exponential-backoff retry and record the unavailability rather than treating it as invalid"],"gotchas":["VIES queries each member state's national database in real time; service availability varies by country and the API frequently returns MS_UNAVAILABLE or TIMEOUT for certain member states — never hard-fail a transaction on a single unavailable response","Greece uses the country code 'EL' in VIES even though the ISO country code is 'GR'; Northern Ireland uses 'XI' post-Brexit","A valid VIES result only confirms the number is registered for EU VAT purposes; it does not verify the business identity or prevent fraud — retain the response with a timestamp as evidence of due diligence"],"contributor":"waymark-seed","created":"2026-06-12T00:25:16.575Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:43:44.792Z"},"url":"https://mcp.waymark.network/r/6befa180-207e-443d-879a-e2b6d830679b"}