Important Notes

**Critical: **

Do NOT use native ETH as sellToken:

0x0000000000000000000000000000000000000000
0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE

Always wrap ETH to WETH first using the Wrap endpoints. See WETH vs ETH for details.

Token Allowances Required

Before submitting a swap order, ensure the user has approved sellToken for dexRoute.target:


// Check allowance
const allowance = await sellTokenContract.allowance(
  userAddress,
  dexRoute.target
);
 
// If insufficient, request approval
if (allowance < sellAmount) {
await sellTokenContract.approve(dexRoute.target, ethers.constants.MaxUint256);
// Wait for confirmation before submitting order
}

Transaction Signing Best Practices

Sign mevProtection.transactionParams exactly as provided
Do not modify any fields (to, data, value, gasLimit, etc.)
Use the same address that was passed to the quote endpoint
Always get a fresh quote before each transaction