{"uid":"cap_KjfWRHELqVtLsL0Nj-FoW","slug":"x402-base-usdc-payment-checker-full-history-deep-scan-84dba173","name":"x402 Base USDC Payment Checker – Full History Deep Scan","description":"Kertivo Index — independent x402 endpoint grades for Base USDC paid delivery. We pay real USDC and check delivery. Grades are earned, never bought. Trust is our keystone.","url":"https://paycheck.hectichustle.workers.dev/check/deep?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"token":{"type":"string","description":"Optional (aliases asset, currency): \"USDC\" or the Base USDC contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 (apexfaucet-style). Any other token is a 400 unsupported_token, not charged. Responses always echo token \"USDC\"."},"txHash":{"type":"string","pattern":"^0x[0-9a-fA-F]{64}$","description":"Base mainnet transaction hash"},"minAmount":{"type":["string","number"],"description":"Optional floor (aliases min_amount, min): payment must be at least this many USDC; unlike expectedAmount it is not exact"},"authorization":{"type":"object","required":["from","nonce"],"properties":{"from":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$"},"nonce":{"type":"string","pattern":"^0x[0-9a-fA-F]{64}$"},"validAfter":{"type":["string","integer"]},"validBefore":{"type":["string","integer"],"description":"unix seconds"}},"description":"Optional EIP-3009 authorization (x402 exact payload) to check when there is no tx or the tx is not found"},"expectedPayTo":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$","description":"Expected recipient (full-address, case-insensitive compare)"},"expectedPayer":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$","description":"Optional expected payer (aliases from, payer): the USDC Transfer's from must equal it"},"selfAddresses":{"type":"array","items":{"type":"string"},"maxItems":10,"description":"Optional: other addresses you control; funding from them counts as self_funded"},"expectedAmount":{"type":["string","number"],"description":"Expected USDC amount, decimal (e.g. \"0.01\")"}}},"responseSchema":{"type":"json","example":{"mode":"live_paid_deep","block":52409752,"found":true,"match":{"ok":true,"payToMatch":true,"amountMatch":true},"funding":{"source":"blockscout","verdict":"external","topFunders":[{"from":"0x86bafb3916943fbba78e7add6c25a230ec27df44","count":2,"total":"161.651325"}],"scannedBlocks":{"to":52409752,"from":0,"history":"full","complete":true,"windowBlocks":52409753}},"payment":{"to":"0x509e55c4f898b43c856fb0e51048b1b7bfbc9ede","from":"0xfc1e390266f3b29179b5d63a7937a689d1e5279a","amount":"1"},"receipt":{"reason":null,"recheck":{"hash":"0x…","hashAlg":"sha256(canonical JSON, keys sorted, no whitespace)","payload":{"v":2,"chain":"eip155:8453","source":"blockscout","blockRange":{"to":52409752,"from":0}}},"verdict":"external","rpcCalls":4,"priceCharged":"0.05 USDC","blocksScanned":{"to":52409752,"from":0,"complete":true}},"summary":"1 USDC from 0xfc1e… to 0x509e… at block 52409752. Matches expected payment. Payer was funded externally.","coverage":{"source":"blockscout","indexer":"blockscout pro (keyed)","complete":true,"rpcCalls":4,"windowTo":52409752,"endpoints":["quicknode (keyed)"],"windowFrom":0,"coveragePct":100,"indexerPages":1,"windowBlocks":52409753,"blocksCovered":52409753,"getLogsChunks":0,"uniqueFunders":1,"historyComplete":true,"inboundTransfers":2},"warnings":[],"confirmed":true,"confirmations":1200}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.05","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.05/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.05","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.05","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_N0h90Vh6y_7ZGDk29Ru3x","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.05","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Performs a full funding-history deep scan of a Base USDC payment by tx hash, verifying match, tracing funder provenance, and detecting address-poisoning risks with the x402 Trust Index.","exampleAgentPrompt":"Do a full deep-scan verification on Base USDC transaction 0xabc123...def456 — I need to confirm it paid exactly 1 USDC to 0x509e55c4f898b43c856fb0e51048b1b7bfbc9ede, and I want the complete funding-history scan to see whether the payer was externally funded or self-funded.","exampleUseCases":[{"title":"Audit new counterparty before releasing goods","prompt":"Before I release the digital goods, do a full deep-scan on Base tx 0xfc1e...279a to confirm it paid exactly 5 USDC to my address 0x509e55c4f898b43c856fb0e51048b1b7bfbc9ede, and tell me whether the payer's wallet was funded externally or by themselves."},{"title":"Detect address-poisoning in a disputed payment","prompt":"A customer claims they paid but I'm not sure they sent to the right address — can you run a deep scan on tx hash 0x87de...a3f1 on Base and check for any address-poisoning warnings, plus confirm the amount was 0.50 USDC to 0x509e55c4f898b43c856fb0e51048b1b7bfbc9ede?"},{"title":"Verify x402 pay-per-call transaction with Trust Index","prompt":"I got a payment via x402 but the client is new to me — please deep scan tx 0xb22c...91fd on Base mainnet, give me their x402 Trust Index grade, and show me who their top funders are so I can assess whether this is a trustworthy payer."}],"resultDescription":"Returns a JSON object with: payment match status (payTo and amount), funding verdict (external vs self-funded), top funders with totals, full block coverage stats (from block 0 to chain tip), address-poisoning warnings, number of confirmations, RPC call count, price charged (0.05 USDC), and a human-readable summary string.","failureModes":["Transaction hash not found on Base mainnet — returns found:false with optional EIP-3009 authorization fallback","Amount or recipient mismatch — returns match.ok:false with specific mismatch fields","Indexer temporarily unavailable — partial coverage with historyComplete:false","Invalid tx hash format — schema validation error before processing","Insufficient x402 payment — 402 response before scan executes","Rate limiting from underlying RPC providers — delayed or partial response"],"whenToPreferThis":"Choose this endpoint over the standard $0.01 checker when you need complete funding-history provenance (scanned from block 0), address-poisoning detection, x402 Trust Index grades, or when auditing a high-value payment from an unknown counterparty. Use the cheaper /check endpoint for simple tx confirmation of known senders.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-17T06:31:11.661Z","isFirstParty":false,"canonicalSlug":"x402-base-usdc-payment-checker-full-history-deep-scan-84dba173"}