{"uid":"cap_zxBbkyB05i6AZAtZsscC0","slug":"base-chain-transaction-simulator-risk-analyzer-e02fa6ea","name":"Base Chain Transaction Simulator & Risk Analyzer","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/v1/chain?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_CwguunF84Ya6882vS9Bmj","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 and analyzes Ethereum Base chain transactions, returning gas estimates, token transfers, balance changes, and a SAFE/UNSAFE verdict before execution.","exampleAgentPrompt":"Before I send this USDC transfer on Base, simulate the transaction from 0xe4be4d0bd82d8e68203deff81f79ede0529f2617 to contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 with calldata 0xa9059cbb... and tell me the gas cost, what token moves where, and whether it's safe to send.","exampleUseCases":[{"title":"Pre-flight check before DeFi swap","prompt":"I'm about to call a Uniswap router on Base — can you simulate the transaction from my address 0xe4be4d0bd82d8e68203deff81f79ede0529f2617 to 0x2626664c2603336E57B271c5C0b26F421741e481 with my swap calldata 0x... and tell me what tokens I'll receive, how much gas it costs in USD, and whether it'll succeed?"},{"title":"Batch contract call dry-run","prompt":"I want to batch simulate these 3 Base contract calls before executing them — sender is 0xe4be4d0bd82d8e68203deff81f79ede0529f2617, calls are an approve then a deposit then a stake. Can you run them in sequence and show me which ones succeed, total gas, and all balance changes?"},{"title":"Revert reason diagnosis","prompt":"My transaction to 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base keeps failing — can you simulate it with sender 0xe4be4d0bd82d8e68203deff81f79ede0529f2617 and calldata 0xa9059cbb... and tell me exactly why it reverts and what the revert reason is?"}],"resultDescription":"Returns a JSON object with: overall success boolean, verdict string (e.g. SAFE_TO_SEND), decoded function name, gas used, fee in ETH and USD, list of token transfers with amounts and symbols, balance changes per address, approval events, revert reason if any, current block number, and suggested next endpoints to call.","failureModes":["Invalid Ethereum address format returns 400 with pattern validation error","Malformed calldata hex returns error on simulation","Simulation of calls that require on-chain state may be inaccurate if state is stale","x402 payment failure (insufficient USDC balance) blocks the call with 402 response","Batch of more than 5 calls rejected","Network congestion on Base may cause stale block data"],"whenToPreferThis":"Use this endpoint when an AI agent or user needs to verify a Base chain transaction's safety, cost, and outcome before committing it on-chain. Ideal for DeFi agents that must preview swaps, transfers, or multi-step contract interactions without risking funds. Prefer over generic RPC eth_call when you need decoded human-readable output (function names, token symbols, USD fees, safe/unsafe verdict) rather than raw hex. No API key required — pay $0.003 USDC per call via x402.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-31T18:42:25.189Z","isFirstParty":false,"canonicalSlug":"base-chain-transaction-simulator-risk-analyzer-e02fa6ea"}