{"uid":"cap_oKM33oHaCWs9JouRRRhhc","slug":"base-transaction-calldata-preflight-inspector-4c5ff26a","name":"Base Transaction Calldata Preflight Inspector","description":"Machine-payable service intelligence for discovering, verifying, and monitoring identity, risk, authorization, execution-preflight, and evidence APIs before autonomous agents spend.","url":"https://base-agent-preflight.bytoken2023.workers.dev/v1/x402/base/transaction-intent","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["to","data"],"properties":{"to":{"type":"string","pattern":"^0x[a-fA-F0-9]{40}$","description":"Base destination contract or account."},"data":{"type":"string","pattern":"^0x(?:[a-fA-F0-9]{2})*$","maxLength":8194,"description":"Hex-encoded EVM calldata."},"value":{"type":"string","pattern":"^[0-9]+$","description":"Native ETH value in wei. Defaults to zero."}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","properties":{"network":{"type":"string"},"product":{"type":"string"},"activity":{"type":"object"},"identity":{"type":"object"},"assessment":{"type":"object"},"provenance":{"type":"object"}}}}}}},"responseSchema":{"type":"json","example":{"network":"eip155:8453","product":"evm-transaction-intent","assessment":{"flags":[],"risk_level":"low","risk_score":0}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","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":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_clNkWJSR_hsfOUPo24-dA","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Decodes and analyzes EVM calldata for a Base transaction before signing, flagging token transfers, approvals, unlimited spending allowances, and unknown function selectors.","exampleAgentPrompt":"Before I sign this Base transaction to contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 with calldata 0x095ea7b3000000000000000000000000deadbeefdeadbeefdeadbeefdeadbeefdeadbeef ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff and no ETH value, can you decode what it actually does and flag if it's an unlimited token approval?","exampleUseCases":null,"resultDescription":"Returns a structured assessment including the decoded activity (e.g. ERC-20 approve, transfer), identity information about the contract, a risk assessment flagging unlimited approvals or unknown selectors, and provenance metadata — all machine-readable so the agent can decide whether to proceed with signing.","failureModes":["Invalid 'to' address format (not a 40-char hex) returns validation error","Malformed or truncated calldata returns decoding failure","Unknown function selector returns flagged unknown-selector warning rather than full decode","Missing required 'to' or 'data' query params returns 400-level error","Payment not included or insufficient USDC triggers x402 payment required response"],"whenToPreferThis":"Use this endpoint when an AI agent is about to sign or broadcast a Base network transaction and needs to understand what the calldata actually does before committing — especially for DeFi interactions involving token approvals, transfers, or unfamiliar contract calls. Prefer over generic ABI decoders when you need a risk-oriented assessment with unlimited-approval and unknown-selector flags specific to the Base chain.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T12:53:38.036Z","isFirstParty":false}