Uniswap · Schema

UserOperation

ERC-4337 v0.8 UserOperation.

BlockchainCryptocurrencyDeFiDecentralized ExchangeLiquiditySwaps

Properties

Name	Type	Description
sender	string	Smart account address that will execute the operation.
nonce	string	Anti-replay nonce from the EntryPoint.
callData	string	ABI-encoded call data for the batch execution.
callGasLimit	string	Gas limit for the main execution call.
verificationGasLimit	string	Gas limit for the verification step.
preVerificationGas	string	Gas to cover bundler overhead and L1 data costs.
maxFeePerGas	string	EIP-1559 max fee per gas.
maxPriorityFeePerGas	string	EIP-1559 max priority fee per gas.
factory	string	Account factory address (present for first-time account deployment).
factoryData	string	Calldata for the account factory.
paymaster	string	Paymaster contract address (present when gas is sponsored).
paymasterVerificationGasLimit	string	Gas limit for paymaster verification.
paymasterPostOpGasLimit	string	Gas limit for paymaster post-operation.
paymasterData	string	Paymaster-specific data.
signature	string	Dummy signature placeholder; the client signs the UserOperation after receiving this response.
eip7702Auth	object

View JSON Schema on GitHub

JSON Schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://raw.githubusercontent.com/api-evangelist/uniswap/refs/heads/main/json-schema/uniswap-user-operation-schema.json",
  "title": "UserOperation",
  "description": "ERC-4337 v0.8 UserOperation.",
  "type": "object",
  "properties": {
    "sender": {
      "type": "string",
      "description": "Smart account address that will execute the operation."
    },
    "nonce": {
      "type": "string",
      "description": "Anti-replay nonce from the EntryPoint."
    },
    "callData": {
      "type": "string",
      "description": "ABI-encoded call data for the batch execution."
    },
    "callGasLimit": {
      "type": "string",
      "description": "Gas limit for the main execution call."
    },
    "verificationGasLimit": {
      "type": "string",
      "description": "Gas limit for the verification step."
    },
    "preVerificationGas": {
      "type": "string",
      "description": "Gas to cover bundler overhead and L1 data costs."
    },
    "maxFeePerGas": {
      "type": "string",
      "description": "EIP-1559 max fee per gas."
    },
    "maxPriorityFeePerGas": {
      "type": "string",
      "description": "EIP-1559 max priority fee per gas."
    },
    "factory": {
      "type": "string",
      "description": "Account factory address (present for first-time account deployment)."
    },
    "factoryData": {
      "type": "string",
      "description": "Calldata for the account factory."
    },
    "paymaster": {
      "type": "string",
      "description": "Paymaster contract address (present when gas is sponsored)."
    },
    "paymasterVerificationGasLimit": {
      "type": "string",
      "description": "Gas limit for paymaster verification."
    },
    "paymasterPostOpGasLimit": {
      "type": "string",
      "description": "Gas limit for paymaster post-operation."
    },
    "paymasterData": {
      "type": "string",
      "description": "Paymaster-specific data."
    },
    "signature": {
      "type": "string",
      "description": "Dummy signature placeholder; the client signs the UserOperation after receiving this response."
    },
    "eip7702Auth": {
      "$ref": "#/components/schemas/Eip7702Authorization"
    }
  },
  "required": [
    "sender",
    "nonce",
    "callData",
    "callGasLimit",
    "verificationGasLimit",
    "preVerificationGas",
    "maxFeePerGas",
    "maxPriorityFeePerGas",
    "signature"
  ]
}

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