prepareApproveWithdrawOrderTxData

Prepare transaction data to approve vault shares for withdrawal via the WithdrawQueue contract.

Before withdrawing, you must approve the WithdrawQueue contract to spend your vault shares. Consider using prepareWithdrawalAuthorization for a higher-level API that handles approval checking automatically.

Import

import { prepareApproveWithdrawOrderTxData } from '@paxoslabs/amplify-sdk'

Usage

// First discover the vault
const [vault] = await getVaultsByConfig({
  yieldType: 'CORE',
  chainId: 1,
})

const txData = await prepareApproveWithdrawOrderTxData({
  vaultName: vault.name,
  wantAssetAddress: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
  withdrawAmount: '100.0',
  chainId: 1,
})

// Execute approval
const hash = await walletClient.writeContract(txData)

Parameters

Parameter	Type	Required	Description
`vaultName`	`string`	Yes	Vault name from `AmplifyVault.name` (e.g. from `getVaultsByConfig()`)
`wantAssetAddress`	`Address`	Yes	Token address you want to receive
`withdrawAmount`	`string`	No	Amount to approve (defaults to max uint256)
`chainId`	`number`	Yes	Chain ID
`shareDecimals`	`number`	No	Pre-fetched vault share decimals (avoids redundant RPC call)

Return Type

Type Definition
Example Response

interface ApproveWithdrawOrderTxData {
  abi: typeof BoringVaultAbi;
  address: `0x${string}`;         // Vault shares (BoringVault) address
  functionName: "approve";
  args: [spender: `0x${string}`, amount: bigint];
}

{
  abi: [/* BoringVault ABI */],
  address: "0x1234567890abcdef...", // Vault shares address
  functionName: "approve",
  args: [
    "0xfedcba0987654321...", // WithdrawQueue address (spender)
    115792089237316195423570985008687907853269984665640564039457584007913129639935n, // Max approval
  ],
}

Examples

Viem
Wagmi

import {
  getVaultsByConfig,
  prepareApproveWithdrawOrderTxData,
  YieldType,
} from "@paxoslabs/amplify-sdk";
import { createWalletClient, createPublicClient, http } from "viem";
import { mainnet } from "viem/chains";

async function approveWithdraw(userAddress: `0x${string}`) {
  const walletClient = createWalletClient({
    account: userAddress,
    chain: mainnet,
    transport: http(),
  });
  const publicClient = createPublicClient({
    chain: mainnet,
    transport: http(),
  });

  const USDC = "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48";

  const [vault] = await getVaultsByConfig({
    yieldType: YieldType.CORE,
    chainId: 1,
  });

  // Approve specific amount
  const txData = await prepareApproveWithdrawOrderTxData({
    vaultName: vault.name,
    wantAssetAddress: USDC,
    withdrawAmount: "100.0",
    chainId: 1,
  });

  const hash = await walletClient.writeContract(txData);
  const receipt = await publicClient.waitForTransactionReceipt({ hash });

  console.log("Approval confirmed:", receipt.transactionHash);
  return hash;
}

import {
  getVaultsByConfig,
  prepareApproveWithdrawOrderTxData,
  YieldType,
} from "@paxoslabs/amplify-sdk";
import { useAccount, useWriteContract, useWaitForTransactionReceipt } from "wagmi";
import { useState } from "react";

function ApproveWithdrawButton() {
  const { address } = useAccount();
  const { writeContractAsync, data: hash } = useWriteContract();
  const { isLoading: isConfirming } = useWaitForTransactionReceipt({ hash });
  const [status, setStatus] = useState("idle");

  async function handleApprove() {
    if (!address) return;

    const USDC = "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48";

    try {
      const [vault] = await getVaultsByConfig({
        yieldType: YieldType.CORE,
        chainId: 1,
      });

      setStatus("Preparing approval...");
      const txData = await prepareApproveWithdrawOrderTxData({
        vaultName: vault.name,
        wantAssetAddress: USDC,
        chainId: 1, // Max approval (no withdrawAmount)
      });

      setStatus("Confirm in wallet...");
      await writeContractAsync(txData);
      setStatus("Waiting for confirmation...");
    } catch (error) {
      setStatus(`Error: ${(error as Error).message}`);
    }
  }

  return (
    <div>
      <button onClick={handleApprove} disabled={isConfirming}>
        {isConfirming ? "Confirming..." : "Approve Withdrawal"}
      </button>
      <p>{status}</p>
    </div>
  );
}

Max vs Specific Approval

Max Approval (Default)

When withdrawAmount is not provided, the SDK approves the maximum amount. This is a one-time approval that covers all future withdrawals:

const [vault] = await getVaultsByConfig({ yieldType: 'CORE', chainId: 1 })

// Max approval - no amount specified
const txData = await prepareApproveWithdrawOrderTxData({
  vaultName: vault.name,
  wantAssetAddress: USDC_ADDRESS,
  chainId: 1,
})

Specific Amount Approval

For tighter security, approve only the amount you intend to withdraw:

// Approve exactly 100 shares
const txData = await prepareApproveWithdrawOrderTxData({
  vaultName: vault.name,
  wantAssetAddress: USDC_ADDRESS,
  withdrawAmount: '100.0',
  chainId: 1,
})

Checking Existing Approval

Before approving, check if approval is already granted:

import {
  getVaultsByConfig,
  isWithdrawalSpendApproved,
  prepareApproveWithdrawOrderTxData,
} from '@paxoslabs/amplify-sdk'

async function ensureApproval(userAddress: `0x${string}`) {
  const USDC = '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48'

  const [vault] = await getVaultsByConfig({ yieldType: 'CORE', chainId: 1 })

  const approvalInfo = await isWithdrawalSpendApproved({
    vaultName: vault.name,
    wantAssetAddress: USDC,
    recipientAddress: userAddress,
    chainId: 1,
  })

  if (approvalInfo.isApproved) {
    console.log(`Already approved. Allowance: ${approvalInfo.allowance}`)
    return null
  }

  // Need to approve first
  return prepareApproveWithdrawOrderTxData({
    vaultName: vault.name,
    wantAssetAddress: USDC,
    chainId: 1,
  })
}

Consider using prepareWithdrawalAuthorization instead, which combines the approval check and approval preparation into a single call.

Error Handling

Error	Description	Resolution
`Vault not found`	No vault matches `vaultName`	Verify vault name via `getVaultsByConfig()`
`Vault chain mismatch`	Vault not on requested chain	Verify chainId matches vault deployment
`BoringVault contract address not configured`	Missing vault config	Check vault configuration
`WithdrawQueue contract address not configured`	Missing queue config	Check vault configuration

getVaultsByConfig - Discover vault names
prepareWithdrawalAuthorization - Unified authorization (recommended)
prepareWithdrawOrderTxData - Submit the withdrawal order
Withdrawals Guide - Complete withdrawal flow

Getting started

Origin - Branded Stablecoins

Amplify - Stablecoin Earn

Access - Borrow

USDG0

prepareApproveWithdrawOrderTxData

Import

Usage

Parameters

Return Type

Examples

Max vs Specific Approval

Max Approval (Default)

Specific Amount Approval

Checking Existing Approval

Error Handling

Getting started

Origin - Branded Stablecoins

Amplify - Stablecoin Earn

Access - Borrow

USDG0

​Import

​Usage

​Parameters

​Return Type

​Examples

​Max vs Specific Approval

​Max Approval (Default)

​Specific Amount Approval

​Checking Existing Approval

​Error Handling

​Related

Import

Usage

Parameters

Return Type

Examples

Max vs Specific Approval

Max Approval (Default)

Specific Amount Approval

Checking Existing Approval

Error Handling

Related