Supported Tokens

The facilitator supports any ERC-20 token on ApeChain that implements EIP-2612 (Permit).

Primary Token

$

USDC (Bridged via Stargate)

RECOMMENDED

The standard stablecoin for agent commerce. Bridged USDC has native EIP-2612 permit support, making it ideal for gasless transactions.

Contract Address0xF1815bd50389c46847f0Bda824eC8da914045D14
Decimals6
Permit Version2
View on ApeScan →

Using USDC in the SDK

The SDK exports the USDC address as a constant for convenience:

import { APECHAIN_USDC, toTokenUnits } from '@x402apechain/sdk';

// APECHAIN_USDC = '0xF1815bd50389c46847f0Bda824eC8da914045D14'

const invoice = {
  chainId: 33139,
  tokenAddress: APECHAIN_USDC,
  recipient: '0x...',
  amount: toTokenUnits('10.00', 6) // 10 USDC = 10000000 units
};

Token Requirements

For a token to work with the X402 facilitator, it must implement the EIP-2612 Permit extension. This adds a permit() function that allows approvals via signatures.

Required Functions

  • • permit(owner, spender, value, deadline, v, r, s)
  • • nonces(owner) - returns current nonce
  • • DOMAIN_SEPARATOR() - for EIP-712 signing

Permit Interface

// IERC20Permit interface (EIP-2612)
interface IERC20Permit {
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    function nonces(address owner) external view returns (uint256);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

Getting USDC on ApeChain

To get USDC on ApeChain for testing or production use:

Bridge from Ethereum/Arbitrum

Use Stargate Finance to bridge USDC from other chains.

Stargate Bridge →

Swap on ApeChain DEX

Swap $APE or other tokens for USDC on ApeChain DEXs.

Camelot DEX →

Adding Custom Tokens

The facilitator can work with any EIP-2612 compatible token. To use a custom token:

  1. Ensure your token implements the Permit interface
  2. Pass the token address in your invoice
  3. The SDK will automatically fetch token metadata (name, decimals, version)
// Using a custom EIP-2612 token
const invoice = {
  chainId: 33139,
  tokenAddress: '0xYourCustomToken...',
  recipient: '0x...',
  amount: toTokenUnits('100', 18) // Adjust decimals for your token
};

await agent.pay({ invoice });

Token Compatibility Check

Before using a new token, verify it supports EIP-2612 by checking if the permit() function exists on the contract. You can do this on ApeScan or by calling the contract directly.