{"uid":"cap__xxXJQl7DOn9ZIp1F10E2","slug":"evm-tx-toolkit-mtree-workers-dev-831f16f2","name":"EVM Transaction Explainer","description":"EVM transaction explainer for Base, Ethereum, Arbitrum, Optimism, and Polygon. Fetch a confirmed transaction by hash and return a human-readable pre-action/post-trade explanation: programs/contracts invoked, method, token balance changes, approvals, fee/gas used, transfer list, and one-line summary. Returns JSON. Price 0.10 USDC on Base via x402. Demo/preview: https://evm-tx-toolkit.mtree.workers.dev/demo/tx/explain. Contact: https://evm-tx-toolkit.mtree.workers.dev/contact.","url":"https://evm-tx-toolkit.mtree.workers.dev/tools/tx_explainer","method":"POST","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method","bodyType","body"],"properties":{"body":{"type":"object","required":["chain","tx_hash"],"properties":{"chain":{"enum":["base","ethereum","arbitrum","optimism","polygon"],"type":"string","example":"base","description":"EVM chain slug"},"tx_hash":{"type":"string","example":"0x0000000000000000000000000000000000000000000000000000000000000000","pattern":"^0x[0-9a-fA-F]{64}$","description":"0x-prefixed transaction hash"}}},"type":{"type":"string","const":"http"},"method":{"enum":["POST"],"type":"string"},"bodyType":{"enum":["json","form-data","text"],"type":"string"}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.1","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"settled","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":"$0.1/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.1","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.1","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_pKE_cf_zSggNBI1SJX_xN","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.1","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Fetches a confirmed EVM transaction by hash and returns a human-readable explanation including contracts invoked, method, token balance changes, approvals, gas used, and a one-line summary","exampleAgentPrompt":"Can you explain what happened in this Ethereum transaction — 0x4a1b2c3d... — which chain it was on (Base), what contracts were called, what tokens moved, and give me a plain-English summary of what the trade did?","exampleUseCases":null,"resultDescription":"A JSON object containing: contracts/programs invoked, the method called, token balance changes before and after the transaction, any ERC-20 approvals granted, gas/fee used, a full transfer list, and a concise one-line human-readable summary of what the transaction did.","failureModes":["Transaction hash not found or not yet confirmed — returns error indicating tx is pending or invalid","Unsupported chain specified — returns error if chain is not Base, Ethereum, Arbitrum, Optimism, or Polygon","Malformed transaction hash — returns validation error","Payment not provided or insufficient — x402 payment required (0.10 USDC on Base) or returns 402 error","RPC timeout or node unavailability — returns upstream error"],"whenToPreferThis":"Use this endpoint when you need a human-readable, structured explanation of a confirmed on-chain EVM transaction — especially for post-trade analysis, audit trails, user-facing trade summaries, or understanding what a historical transaction actually did. Prefer this over raw RPC calls when you want pre-parsed token balance changes, approval detection, and a natural-language summary without writing your own decoder.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T06:41:21.761Z","isFirstParty":false}