API Reference

Complete API documentation for @tetherto/wdk-protocol-bridge-usdt0-evm

Class

Description

Methods

Main class for bridging USDT0 tokens across blockchains. Extends BridgeProtocol from @tetherto/wdk-wallet/protocols.

Constructor, Methods

Usdt0ProtocolEvm

The main class for bridging USDT0 tokens across different blockchains using the LayerZero protocol. Extends BridgeProtocol from @tetherto/wdk-wallet/protocols.

Constructor

new Usdt0ProtocolEvm(account, config?)

Parameters:

account (WalletAccountEvm | WalletAccountEvmErc4337 | WalletAccountReadOnlyEvm | WalletAccountReadOnlyEvmErc4337): The wallet account to use for bridge operations
config (BridgeProtocolConfig, optional): Configuration object
- bridgeMaxFee (bigint, optional): Maximum total bridge cost in wei

Example:

import Usdt0ProtocolEvm from '@tetherto/wdk-protocol-bridge-usdt0-evm'
import { WalletAccountEvm } from '@tetherto/wdk-wallet-evm'

const account = new WalletAccountEvm(seedPhrase, {
  provider: 'https://eth-mainnet.g.alchemy.com/v2/your-api-key'
})

const bridgeProtocol = new Usdt0ProtocolEvm(account, {
  bridgeMaxFee: 1000000000000000n // Maximum bridge fee in wei
})

Methods

Method

Description

Returns

Throws

bridge(options, config?)

Bridges tokens to another blockchain

Promise<BridgeResult>

If no provider or fee exceeds max

quoteBridge(options, config?)

Estimates the cost of a bridge operation

Promise<Omit<BridgeResult, 'hash' | 'approveHash'>>

If no provider

`bridge(options, config?)`

Bridges tokens to a different blockchain using the USDT0 protocol.

Parameters:

options (BridgeOptions): Bridge operation options
- targetChain (string): Destination chain name
- recipient (string): Address that will receive the bridged tokens
- token (string): Token contract address on source chain
- amount (bigint): Amount to bridge in token base units
config (Pick<EvmErc4337WalletConfig, 'paymasterToken'> & Pick<BridgeProtocolConfig, 'bridgeMaxFee'>, optional): Override configuration for ERC-4337 accounts
- paymasterToken (string, optional): Token to use for paying gas fees
- bridgeMaxFee (bigint, optional): Override maximum bridge fee

Returns: Promise<BridgeResult> - Bridge operation result

Throws:

Error if account is read-only
Error if no provider is configured
Error if bridge fee exceeds maximum allowed

Example:

// Standard EVM account
const result = await bridgeProtocol.bridge({
  targetChain: 'arbitrum',
  recipient: '0x...', // Recipient address
  token: '0x...', // USDT contract address
  amount: 1000000000000000000n
})

console.log('Bridge hash:', result.hash)
console.log('Approve hash:', result.approveHash)
console.log('Reset allowance hash:', result.resetAllowanceHash) // Only for USDT on Ethereum
console.log('Total fee:', result.fee)
console.log('Bridge fee:', result.bridgeFee)

// ERC-4337 account
const result2 = await bridgeProtocol.bridge({
  targetChain: 'arbitrum',
  recipient: '0x...', // Recipient address
  token: '0x...', // USDT contract address
  amount: 1000000000000000000n
}, {
  paymasterToken: '0x...', // Paymaster token address
  bridgeMaxFee: 1000000000000000n
})

console.log('Bridge hash:', result2.hash) // Single hash for bundled operations
console.log('Total fee:', result2.fee)
console.log('Bridge fee:', result2.bridgeFee)

`quoteBridge(options, config?)`

Estimates the cost of a bridge operation without executing it.

Parameters:

options (BridgeOptions): Bridge operation options (same as bridge method)
config (Pick<EvmErc4337WalletConfig, 'paymasterToken'>, optional): Override configuration for ERC-4337 accounts
- paymasterToken (string, optional): Token to use for paying gas fees

Returns: Promise<Omit<BridgeResult, 'hash' | 'approveHash'>> - Bridge cost estimate

Throws: Error if no provider is configured

Example:

const quote = await bridgeProtocol.quoteBridge({
  targetChain: 'polygon',
  recipient: '0x...', // Recipient address
  token: '0x...', // USDT contract address
  amount: 1000000000000000000n
})

console.log('Estimated fee:', quote.fee, 'wei')
console.log('Bridge fee:', quote.bridgeFee, 'wei')

// Check if fees are acceptable
if (quote.fee + quote.bridgeFee > 1000000000000000n) {
  console.log('Bridge fees too high')
} else {
  // Proceed with bridge
  const result = await bridgeProtocol.bridge({
    targetChain: 'polygon',
    recipient: '0x...', // Recipient address
    token: '0x...', // USDT contract address
    amount: 1000000000000000000n
  })
}

Types

BridgeOptions

interface BridgeOptions {
  targetChain: string;              // Destination chain name
  recipient: string;                // Address that will receive bridged tokens
  token: string;                    // Token contract address on source chain
  amount: bigint;                   // Amount to bridge in token base units
}

BridgeResult

interface BridgeResult {
  hash: string;                     // Main bridge transaction hash
  fee: bigint;                      // Total gas cost in wei
  bridgeFee: bigint;                // Bridge protocol fee in wei
  approveHash?: string;             // Approve transaction hash (standard accounts only)
  resetAllowanceHash?: string;      // Reset allowance hash (USDT on Ethereum only)
}

BridgeProtocolConfig

interface BridgeProtocolConfig {
  bridgeMaxFee?: bigint;            // Maximum total bridge cost in wei
}

EvmErc4337WalletConfig

interface EvmErc4337WalletConfig {
  paymasterToken?: string;          // Token to use for paying gas fees
}

Supported Chains

The bridge protocol supports the following chains:

Source Chains (EVM):

'ethereum' (Chain ID: 1)
'arbitrum' (Chain ID: 42,161) - ERC-4337 support
'polygon' (Chain ID: 137)
'berachain' (Chain ID: 80,094)
'ink' (Chain ID: 57,073)

Destination Chains:

'ethereum' (Chain ID: 1)
'arbitrum' (Chain ID: 42,161)
'polygon' (Chain ID: 137)
'berachain' (Chain ID: 80,094)
'ink' (Chain ID: 57,073)
'ton' (Chain ID: 30,343)
'tron' (Chain ID: 728,126,428)

Error Handling

The bridge protocol throws specific errors for different failure cases:

try {
  const result = await bridgeProtocol.bridge({
    targetChain: 'arbitrum',
    recipient: '0x...', // Recipient address
    token: '0x...', // USDT contract address
    amount: 1000000000000000000n
  })
} catch (error) {
  if (error.message.includes('not supported')) {
    console.error('Chain or token not supported')
  }
  if (error.message.includes('Exceeded maximum fee')) {
    console.error('Bridge fee too high')
  }
  if (error.message.includes('must be connected to a provider')) {
    console.error('Wallet not connected to blockchain')
  }
  if (error.message.includes('requires the protocol to be initialized with a non read-only account')) {
    console.error('Cannot bridge with read-only account')
  }
  if (error.message.includes('cannot be equal to the source chain')) {
    console.error('Cannot bridge to the same chain')
  }
}

Usage Examples

Basic Bridge Operation

import Usdt0ProtocolEvm from '@tetherto/wdk-protocol-bridge-usdt0-evm'
import { WalletAccountEvm } from '@tetherto/wdk-wallet-evm'

async function bridgeTokens() {
  // Create wallet account
  const account = new WalletAccountEvm(seedPhrase, {
    provider: 'https://eth-mainnet.g.alchemy.com/v2/your-api-key'
  })
  
  // Create bridge protocol
  const bridgeProtocol = new Usdt0ProtocolEvm(account, {
    bridgeMaxFee: 1000000000000000n
  })
  
  // Get quote first
  const quote = await bridgeProtocol.quoteBridge({
    targetChain: 'arbitrum',
    recipient: '0x...', // Recipient address
    token: '0x...', // USDT contract address
    amount: 1000000000000000000n
  })
  
  console.log('Bridge quote:', quote)
  
  // Execute bridge
  const result = await bridgeProtocol.bridge({
    targetChain: 'arbitrum',
    recipient: '0x...', // Recipient address
    token: '0x...', // USDT contract address
    amount: 1000000000000000000n
  })
  
  console.log('Bridge result:', result)
  
  return result
}

Multi-Chain Bridge

async function bridgeToMultipleChains(bridgeProtocol) {
  const chains = ['arbitrum', 'polygon', 'ethereum']
  const token = '0x...' // USDT contract address
  const amount = 1000000000000000000n
  const recipient = '0x...' // Recipient address
  
  const results = []
  
  for (const chain of chains) {
    try {
      // Get quote
      const quote = await bridgeProtocol.quoteBridge({
        targetChain: chain,
        recipient,
        token,
        amount
      })
      
      console.log(`Bridge to ${chain}:`, quote)
      
      // Execute bridge
      const result = await bridgeProtocol.bridge({
        targetChain: chain,
        recipient,
        token,
        amount
      })
      
      results.push({ chain, result })
      console.log(`Bridge to ${chain} successful:`, result.hash)
      
    } catch (error) {
      console.error(`Bridge to ${chain} failed:`, error.message)
    }
  }
  
  return results
}

ERC-4337 Gasless Bridge

import { WalletAccountEvmErc4337 } from '@tetherto/wdk-wallet-evm-erc-4337'

async function gaslessBridge() {
  // Create ERC-4337 account
  const account = new WalletAccountEvmErc4337(seedPhrase, {
    provider: 'https://arb1.arbitrum.io/rpc',
    paymasterToken: '0x...' // Paymaster token address
  })
  
  // Create bridge protocol
  const bridgeProtocol = new Usdt0ProtocolEvm(account, {
    bridgeMaxFee: 1000000000000000n
  })
  
  // Bridge with gasless transactions
  const result = await bridgeProtocol.bridge({
    targetChain: 'polygon',
    recipient: '0x...', // Recipient address
    token: '0x...', // USDT contract address
    amount: 1000000000000000000n
  }, {
    paymasterToken: '0x...' // Paymaster token address
  })
  
  console.log('Gasless bridge result:', result)
  return result
}

Node.js Quickstart

Get started with WDK in a Node.js environment

WDK Bridge USDT0 EVM Protocol Configuration

Get started with WDK's Bridge USDT0 EVM Protocol configuration

WDK Bridge USDT0 EVM Protocol Usage

Get started with WDK's Bridge USDT0 EVM Protocol usage

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Table of Contents

Usdt0ProtocolEvm

Constructor

Methods

bridge(options, config?)

quoteBridge(options, config?)

Types

BridgeOptions

BridgeResult

BridgeProtocolConfig

EvmErc4337WalletConfig

Supported Chains

Error Handling

Usage Examples

Basic Bridge Operation

Multi-Chain Bridge

ERC-4337 Gasless Bridge

Need Help?

`bridge(options, config?)`

`quoteBridge(options, config?)`