alchemy_simulateExecution

1 curl -X POST https://eth-mainnet.g.alchemy.com/v2/{apiKey} \ 2 -H "Content-Type: application/json" \ 3 -d '{ 4 "jsonrpc": "2.0", 5 "method": "alchemy_simulateExecution", 6 "params": [ 7 "FLAT", 8 { 9 "from": "0x0dd7eef07982749410eceaa721cdc8ff3167fc9b", 10 "to": "0x68b3465833fb72a70ecdf485e0e4c7bd8665fc45", 11 "data": "0x5ae401dc00000000000000000000000000000000000000000000000000000000634ef02f...", 12 "gas": "0x22710", 13 "gasPrice": "0x3b9aca00" 14 }, 15 "latest" 16 ], 17 "id": 1 18 }'

1 { 2 "jsonrpc": "2.0", 3 "id": "1", 4 "result": { 5 "calls": [ 6 { 7 "type": "CALL", 8 "from": "0x0dd7eef07982749410eceaa721cdc8ff3167fc9b", 9 "to": "0x68b3465833fb72a70ecdf485e0e4c7bd8665fc45", 10 "value": "0x0", 11 "gas": "0x22710", 12 "gasUsed": "0x1ab62", 13 "input": "0x5ae401dc0000000000...", 14 "output": "0x000000000000000000000000000000000000000000...", 15 "decoded": { 16 "authority": "ETHERSCAN", 17 "methodName": "multicall", 18 "inputs": [ 19 { 20 "name": "deadline", 21 "type": "uint256", 22 "value": "1666117679" 23 }, 24 { 25 "name": "data", 26 "type": "bytes[]", 27 "value": "0x04e45aaf000000000000000000000000..." 28 } 29 ], 30 "outputs": [ 31 { 32 "name": "", 33 "type": "bytes[]", 34 "value": "0x000000000000000000000000000000000000000000..." 35 } 36 ] 37 } 38 } 39 ], 40 "logs": [ 41 { 42 "address": "0x6b175474e89094c44da98b954eedeac495271d0f", 43 "data": "0x0000000000000000000000000000000000000000000000001bc097e5badd8f46", 44 "topics": [ 45 "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef", 46 "0x48da0965ab2d2cbf1c17c09cfb5cbe67ad5b1406", 47 "0xdd7eef07982749410eceaa721cdc8ff3167fc9b" 48 ], 49 "decoded": { 50 "authority": "ETHERSCAN", 51 "eventName": "Transfer", 52 "inputs": [ 53 { 54 "name": "src", 55 "type": "address", 56 "value": "0x48da0965ab2d2cbf1c17c09cfb5cbe67ad5b1406", 57 "indexed": true 58 }, 59 { 60 "name": "dst", 61 "type": "address", 62 "value": "0x0dd7eef07982749410eceaa721cdc8ff3167fc9b", 63 "indexed": true 64 }, 65 { 66 "name": "wad", 67 "type": "uint256", 68 "value": "1999765247490887494", 69 "indexed": false 70 } 71 ] 72 } 73 } 74 ], 75 "error": "", 76 "revertReason": null 77 } 78 }

Simulates a single transaction’s execution and returns decoded traces/logs.

Path parameters

apiKeystringRequired

Request

This endpoint expects an object.

formatenumRequired

Specifies whether to return a ‘NESTED’ or ‘FLAT’ call structure.

Allowed values:

transactionobjectRequired

Transaction object to simulate.

blockTagenumRequired

The block context to use: ‘latest’, ‘safe’, ‘finalized’, or ‘earliest’.

Allowed values:

Response

The decoded execution traces and logs produced by simulating the transaction.

callslist of objects

logslist of objects

errorstringOptional

If the transaction would revert, error explains the reason

revertReasonstringOptional

The reason why a transaction would revert. Provides details about potential transaction failure before execution.