{"slug":"x402-research-iota-vercel-app-api-x402-invoice-decode-0616db","title":"Use before paying any x402 invoice","host":"x402-research-iota.vercel.app","method":"GET","resource":"https://x402-research-iota.vercel.app/api/x402/invoice-decode","category":"search","description":"Use before paying any x402 invoice: decodes a base64 PAYMENT-REQUIRED header (query ?header= or JSON body {header}) and checks scheme exact, Base mainnet, Base USDC asset, payTo (EOA/contract/EIP-7702), human amount, timeout; returns verdict ok/warn/fail with reasons. Errors: 400 invalid header. Rea","price_listed":0.02,"price_asked":null,"state":"no_terms","state_label":"Answers HTTP 400 without x402 payment terms","checks_7d":1,"answered_7d":0,"latency_ms_median":null,"reported_calls_30d":0,"reported_payers_30d":0,"networks":["eip155:8453"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"method":"GET","queryParams":{"header":"eyJ4NDAyVmVyc2lvbiI6Miwi..."},"type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"method":{"enum":["GET"],"type":"string"},"queryParams":{"properties":{"header":{"description":"base64 PAYMENT-REQUIRED header value","type":"string"}},"required":["header"],"type":"object"},"type":{"const":"http","type":"string"}},"required":["type","method"],"type":"object"},"output":{"properties":{"example":{"properties":{"accepts":{"items":{"type":"object"},"type":"array"},"reasons":{"items":{"type":"string"},"type":"array"},"resource":{"type":"object"},"signed":{"type":"boolean"},"verdict":{"enum":["ok","warn","fail"],"type":"string"},"x402Version":{"type":"number"}},"type":"object"},"type":{"type":"string"}},"required":["type"],"type":"object"}},"required":["input"],"type":"object"},"history":[{"day":"2026-10-25","reachable":true,"status":400,"valid_402":false,"asked_usdc":null,"price_match":null,"latency_ms":516,"error":null}],"description_full":"Use before paying any x402 invoice: decodes a base64 PAYMENT-REQUIRED header (query ?header= or JSON body {header}) and checks scheme exact, Base mainnet, Base USDC asset, payTo (EOA/contract/EIP-7702), human amount, timeout; returns verdict ok/warn/fail with reasons. Errors: 400 invalid header. Read-only; never signs or pays.","last_updated":"2026-10-25T13:32:35.938Z","schemes":["exact"]}