{"slug":"api-zfinia-com-x402-v1-reverse-dns-consistency-audit-602519","title":"Check the address, reverse name and forward address triple that receivers actual","host":"api.zfinia.com","method":"POST","resource":"https://api.zfinia.com/x402/v1/reverse-dns-consistency-audit","category":"code","description":"Check the address, reverse name and forward address triple that receivers actually evaluate. Reports an address with no reverse name, which many receivers refuse before the message body is sent; a reverse name that resolves to a different address, so forward confirmation fails, which is worse than h","price_listed":0.14,"price_asked":null,"state":"down","state_label":"Not answering","checks_7d":1,"answered_7d":0,"latency_ms_median":null,"reported_calls_30d":1,"reported_payers_30d":1,"networks":["eip155:8453"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"body":{"expected_domain":"example.test","hosts":[{"address":"203.0.113.10","forward_addresses":["203.0.113.10"],"helo":"mx1.example.test","ptr":"mx1.example.test"},{"address":"203.0.113.11","forward_addresses":["203.0.113.99"],"helo":"mx2.example.test","ptr":"mx2.example.test"},{"address":"198.51.100.7","forward_addresses":["198.51.100.7"],"helo":"mail.example.test","ptr":"198-51-100-7.static.hosting-vendor.test"},{"address":"192.0.2.44"}]},"bodyType":"json","method":"POST","type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"body":{"additionalProperties":false,"properties":{"expected_domain":{"maxLength":253,"type":"string"},"hosts":{"items":{"additionalProperties":false,"properties":{"address":{"maxLength":64,"type":"string"},"forward_addresses":{"items":{"maxLength":64,"type":"string"},"maxItems":50,"minItems":1,"type":"array"},"helo":{"maxLength":253,"type":"string"},"ptr":{"maxLength":253,"type":"string"}},"required":["address"],"type":"object"},"maxItems":500,"minItems":1,"type":"array"}},"required":["hosts"],"type":"object"},"bodyType":{"enum":["json","form-data","text"],"type":"string"},"method":{"enum":["POST"],"type":"string"},"type":{"const":"http","type":"string"}},"required":["type","method","bodyType","body"],"type":"object"},"output":{"properties":{"example":{"type":"object"},"type":{"type":"string"}},"required":["type"],"type":"object"}},"required":["input"],"type":"object"},"history":[{"day":"2026-10-04","reachable":false,"status":null,"valid_402":false,"asked_usdc":null,"price_match":null,"latency_ms":null,"error":"TimeoutError"}],"description_full":"Check the address, reverse name and forward address triple that receivers actually evaluate. Reports an address with no reverse name, which many receivers refuse before the message body is sent; a reverse name that resolves to a different address, so forward confirmation fails, which is worse than having none because it looks configured; a provider-generated name; and a HELO that does not match the reverse name.","last_updated":"2026-10-04T08:43:47.844Z","schemes":["exact"]}