Skip to content
Docs

sendUserOperation

Broadcasts a User Operation to the Bundler. This method allows you to execute one or more transactions through your Smart Account.

Usage

example.ts
import { nexusClient } from "./nexusClient"
import { parseEther } from 'viem'
 
// Simple ETH transfer
const hash = await nexusClient.sendUserOperation({
  calls: [{
    to: '0x70997970c51812dc3a010c7d01b50e0d17dc79c8',
    value: parseEther('1')
  }]
})
 
// Multiple calls including contract interaction
const hash2 = await nexusClient.sendUserOperation({
  calls: [
    { 
      to: '0x70997970c51812dc3a010c7d01b50e0d17dc79c8', 
      value: parseEther('1') 
    }, 
    { 
      abi: wagmiAbi, 
      functionName: 'mint', 
      to: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2', 
    }
  ] 
})

Parameters

Required Parameters

  • calls ({ data?: Hex, to: Address, value?: bigint } | { abi: Abi, functionName: string, args: unknown[], to: Address, value?: bigint })[]: Array of transactions to execute

Optional Parameters

  • maxFeePerGas bigint: Maximum fee per gas for User Operation execution
  • maxPriorityFeePerGas bigint: Maximum priority fee per gas
  • callGasLimit bigint: Amount of gas to allocate for the main execution call
  • verificationGasLimit bigint: Amount of gas to allocate for the verification step
  • preVerificationGas bigint: Extra gas to pay the Bundler
  • nonce bigint: Nonce for the User Operation
  • paymaster Address | true | PaymasterClient | PaymasterAction: Paymaster configuration for gas sponsorship
  • paymasterData Hex: Call data to execute on the Paymaster contract (when paymaster is an address)
  • paymasterVerificationGasLimit bigint: Gas limit for paymaster validation
  • paymasterPostOpGasLimit bigint: Gas limit for paymaster post-operation code
  • signature Hex: Custom signature for the User Operation

Response

  • Promise<Hash>: Returns the User Operation hash

Paymaster Configuration

The paymaster parameter supports multiple configurations:

// Using a Paymaster address
const hash = await nexusClient.sendUserOperation({
  calls: [...],
  paymaster: '0x942fD5017c0F60575930D8574Eaca13BEcD6e1bB',
  paymasterData: '0xdeadbeef'
})
 
// Using a Paymaster Client
const hash = await nexusClient.sendUserOperation({
  calls: [...],
  paymaster: paymasterClient,
  paymasterContext: {
    policyId: 'abc123'
  }
})

Error Handling

The method will throw an error if:

  • The client account is not properly configured
  • User operation preparation fails
  • Bundler rejects the operation
  • Gas estimation fails

Related Methods