{"uid":"cap_bOT93gEWEihuI95I3M1__","slug":"preflight-decode-tx-calldata-9656afbd","name":"PreFlight – Decode TX Calldata","description":"Pre-trade & pre-sign checks for autonomous agents: everything an agent verifies BEFORE signing a transaction — token due diligence, calldata red-flag decoding, oracle freshness, holder concentration, bridge routing with executable calldata, cross-venue perp funding, gas and price sanity checks. EVM chains: Ethereum, Base, Arbitrum, Optimism.","url":"https://meryol-agenticmarket-x402.hf.space/decode/tx","method":"POST","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method","bodyType","body"],"properties":{"body":{"required":["chain","to","data"],"properties":{"to":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$"},"data":{"type":"string","pattern":"^0x[0-9a-fA-F]+$"},"chain":{"enum":["ethereum","base","arbitrum","optimism"],"type":"string"},"value":{"type":"string"}}},"type":{"type":"string","const":"http"},"method":{"enum":["POST","PUT","PATCH"],"type":"string"},"bodyType":{"enum":["json","form-data","text"],"type":"string"}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","required":["chain","to","selector","summary","red_flags"],"properties":{"to":{"type":"string"},"args":{"type":"array"},"chain":{"type":"string"},"summary":{"type":"string"},"selector":{"type":"string"},"red_flags":{"type":"array","items":{"type":"string"}},"signature":{"type":"string"}}}}}}},"responseSchema":{"type":"json","example":{"to":"0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48","args":[{"type":"address","value":"0xdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef"},{"type":"uint256","value":"115792089237316195423570985008687907853269984665640564039457584007913129639935"}],"chain":"ethereum","summary":"Approve spender 0xdeadbeef... to spend UNLIMITED on token USDC","selector":"095ea7b3","red_flags":["unlimited_token_approval","approval_to_unverified_contract"],"signature":"approve(address,uint256)"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.003","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"registry","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":"$0.003/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_qRqkWJ4n_h4U1knkDUUhh","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.003","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Decodes EVM transaction calldata and flags red-flag patterns (e.g. unlimited approvals, unverified spenders) before an agent signs","exampleAgentPrompt":"Before I sign this transaction, decode the calldata for me and flag any red flags — the contract is 0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48 on Ethereum and the calldata starts with 095ea7b3 approving 0xdeadbeef... for a max uint256 amount.","exampleUseCases":null,"resultDescription":"Returns the decoded function signature, selector, typed argument list (with types and values), a human-readable summary of what the transaction does, and an array of red-flag labels such as 'unlimited_token_approval' or 'approval_to_unverified_contract'.","failureModes":["Malformed or non-hex calldata returns a decode error","Unknown function selector not in ABI database returns partial decode","Unsupported chain identifier returns 400 validation error","Network timeout or HuggingFace Space cold-start latency spike","Payment not attached or insufficient USDC returns 402 error"],"whenToPreferThis":"Use this endpoint when an AI agent needs to understand and safety-check a raw EVM transaction before submitting it — especially for token approvals, DeFi interactions, or any calldata received from an untrusted source. Prefer this over generic ABI decoders when you need red-flag detection (unlimited approvals, unverified spenders) alongside decoding in a single pre-sign check.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-13T18:36:46.575Z","isFirstParty":false}