{"uid":"cap_QvXpQhy4FPmNCGLsEYzuv","slug":"tenderly-transaction-simulation-base-via-x402-dc02e2e3","name":"Tenderly Transaction Simulation (Base) via x402","description":"Pay-per-call crypto microdata for trading/onchain AI agents via x402 (USDC on Base): Base gas, token risk, balances, multi-venue prices, Hyperliquid book/funding, kimchi premium. No API keys.","url":"https://kr-x402-mvp.kgy5612.workers.dev/api/tenderly/simulate?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","properties":{"to":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$","examples":["0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"],"description":"Target contract or recipient"},"data":{"type":"string","pattern":"^0x([0-9a-fA-F]{2})*$","description":"Calldata (default 0x)"},"from":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$","examples":["0xe4be4d0bd82d8e68203deff81f79ede0529f2617"],"description":"Sender (signer) address"},"calls":{"type":"string","description":"URL-encoded JSON array of up to 5 {to,data,value_eth|value} run in order from the same sender"},"value_eth":{"type":"string","examples":["0.01"],"description":"ETH to send, decimal (default 0)"}},"additionalProperties":false}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"from":"0xe4be4d0bd82d8e68203deff81f79ede0529f2617","next":["/crypto/base-gas","/crypto/tx-status?hash="],"block":53272234,"calls":[{"to":"0x833589fcd6edb6e08f4c7c32d4f71b54bda02913","index":0,"success":true,"function":"transfer(address,uint256)","gas_used":45047,"revert_reason":null}],"chain":"base","flags":[],"fee_eth":5e-7,"fee_usd":0.0019,"success":true,"summary":"1 call succeeds; sender sends 0.001 USDC","verdict":"SAFE_TO_SEND","approvals":[],"transfers":[{"to":"0xa587d73489f8f09d1975f1ddbb1c61c93e8fa9d7","from":"0xe4be4d0bd82d8e68203deff81f79ede0529f2617","token":"0x833589fcd6edb6e08f4c7c32d4f71b54bda02913","amount":0.001,"symbol":"USDC"}],"gas_used_total":45047,"sender_changes":{"USDC":-0.001},"balance_changes":{"0xa587d73489f8f09d1975f1ddbb1c61c93e8fa9d7":{"USDC":0.001},"0xe4be4d0bd82d8e68203deff81f79ede0529f2617":{"USDC":-0.001}}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.003","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":"$0.003/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_UaX8x-EoajEizCPcMMnMn","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.003","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Simulates one or more Ethereum/Base transactions using Tenderly, returning safety verdict, token transfers, gas cost, and balance changes before broadcasting on-chain.","exampleAgentPrompt":"Before I send 0.001 USDC to 0xa587d73489f8f09d1975f1ddbb1c61c93e8fa9d7 from my wallet 0xe4be4d0bd82d8e68203deff81f79ede0529f2617 on Base, simulate the transaction and tell me if it's safe, what the gas cost will be in USD, and what token balances will change.","exampleUseCases":[{"title":"Pre-flight check before USDC transfer","prompt":"I'm about to send 50 USDC from 0xe4be4d0bd82d8e68203deff81f79ede0529f2617 to 0xa587d73489f8f09d1975f1ddbb1c61c93e8fa9d7 on Base — simulate it first and tell me if it will succeed, what the gas fee is in USD, and exactly which balances change."},{"title":"Debug reverting smart contract call","prompt":"My contract call to 0x833589fcd6edb6e08f4c7c32d4f71b54bda02913 with calldata 0xa9059cbb000000000000000000000000a587d73489f8f09d1975f1ddbb1c61c93e8fa9d70000000000000000000000000000000000000000000000000000000000000064 from 0xe4be4d0bd82d8e68203deff81f79ede0529f2617 keeps failing — simulate it and tell me the revert reason."},{"title":"Batch multi-step DeFi sequence preview","prompt":"I want to simulate two calls in sequence on Base from 0xe4be4d0bd82d8e68203deff81f79ede0529f2617: first approve USDC to the swap router, then execute the swap — can you dry-run both and show me the safety verdict and total gas cost before I broadcast?"}],"resultDescription":"Returns a JSON object with: overall success/failure verdict (SAFE_TO_SEND or revert), per-call breakdown (function decoded, gas used, revert reason if any), list of token transfers with amounts and symbols, net balance changes per address, estimated fee in ETH and USD, and block number of simulation. Also includes suggested next endpoints to call.","failureModes":["Invalid Ethereum address format returns schema validation error","Malformed calldata hex string rejected before simulation","Simulation itself may succeed even if on-chain state has diverged since block snapshot","Network errors to Tenderly backend return 5xx","x402 payment failure if agent wallet has insufficient USDC on Base","Batch of more than 5 calls rejected by schema constraint"],"whenToPreferThis":"Choose this endpoint when an AI agent needs to dry-run a Base/Ethereum transaction before broadcasting — especially to check safety (SAFE_TO_SEND verdict), decode token transfers, estimate gas in USD, or diagnose revert reasons. Prefer over raw eth_call when you need a human-readable summary with decoded function names, transfer lists, and balance deltas. Ideal for autonomous trading agents that must validate each step before committing funds on-chain. No API key required; pay per call with USDC via x402.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-11-02T18:33:20.592Z","isFirstParty":false,"canonicalSlug":"tenderly-transaction-simulation-base-via-x402-dc02e2e3"}