USDT0 (Stellar to EVM networks)

client.usdt0 sends USDT0, Tether's omnichain USDT, from Stellar to an EVM network through LayerZero's OFT. Ethereum (eth) receives native USDT; every other network receives USDT0. Every route takes an EVM recipient (0x + 40 hex).

• Mainnet only. A dev (testnet) key gets available: false and no routes from routes(), and 400 network_unsupported from quote() and create().
• Fees, in XLM, paid by the holder: LayerZero's messaging fee (nativeFee; the transaction offers nativeFeeLimit, 20% more, and the unused part is refunded in the same transaction) and the Stellar network fee (networkFee). Any plan commission shows in feeBps / feeAmount (0 when the deployment has no fee wrapper).
• Dust: the OFT carries 6 decimals and the asset has 7, so a 7th decimal of amount is dust that stays in the account.

Signing works like a swap: the API builds the one Soroban transaction, the account that holds the USDT0 signs it, and submit relays the signed XDR. The API never holds a key.

import { Usdt0TransferStatus } from '@cosmosapp/pay_sdk';

const { available, routes } = await client.usdt0.routes();
// routes: [{ chain: 'eth', name: 'Ethereum', eid: 30101, receives: 'USDT' }, ...]

const quote = await client.usdt0.quote({ to: 'arb', amount: '12.5' }); // persists nothing
// { amountSent, amountReceived, dust, nativeFee, nativeFeeLimit, minAmount, maxAmount, ... }

const transfer = await client.usdt0.create({
  source: 'G...',            // holds the USDT0, signs, pays the XLM fees
  to: 'arb',                 // a route's `chain`
  recipient: '0x5aAe...',    // EVM address credited
  amount: '12.5',
  idempotencyKey: 'payout-77', // optional, sent as the Idempotency-Key header too
  // merchantFee: { bps: 50, wallet: 'G...' }, // optional, in USDT0; needs the fee wrapper
});

// Sign transfer.xdr with the holder's wallet (e.g. Freighter), or open the SEP-7
// link transfer.uri. transfer.qr is usually null: a Soroban transaction is too
// large for a QR.
const outcome = await transfer.submit({ signedXdr });
// { submitted, status, txHash, reason, transfer }; the instance is updated in place

await transfer.fetch(); // the API refreshes it from the ledger and LayerZero Scan
transfer.status;        // PENDING -> SUBMITTED -> DELIVERED (or FAILED / EXPIRED)
transfer.isFinal;       // DELIVERED, FAILED or EXPIRED

Delivery takes about 27 minutes on every route (LayerZero's verifiers wait for Stellar confirmations). Once DELIVERED, destinationTxHash is the destination network's transaction; guid, scanStatus and scanUrl follow it on LayerZero Scan.

A submit the network refuses leaves the transfer PENDING (submitted: false, reason): fix the cause and submit again until expiresAt. A transaction that fails on the ledger moves it to FAILED (failureReason).

const page = await client.usdt0.list({ status: Usdt0TransferStatus.Delivered, take: 20 });
// { items: Usdt0Transfer[], total, take, skip }, newest first, as last refreshed
const one = await client.usdt0.fetch('cm2u0t0transfer0000000001'); // refreshes it
const raw = await client.usdt0.submit(one.id, { signedXdr });       // manager form

With the shared public key

A client built with the shared public key (an open-source wallet) gets a publicToken from create. The Usdt0Transfer keeps it and sends it as X-Record-Token on its own fetch() and submit(); with the manager, pass { recordToken } to fetch(id, { recordToken }) and submit(id, { signedXdr, recordToken }). Without it the API answers 404. list() is refused to the shared public key. Any other key ignores the token.

Usdt0Transfer accessors

id, status, network, source, to, eid, receives, recipient, amount, amountSent, amountReceived, dust, nativeFee, nativeFeeLimit, networkFee, feeBps, feeAmount, feeWallet, xdr, uri, qr, txHash, guid, destinationTxHash, scanStatus, scanUrl, failureReason, merchantFee, idempotencyKey, expiresAt, submittedAt, createdAt, updatedAt, publicToken, plus isPending, isDelivered, isFinal.

References

• Usdt0Transfer: A USDT0 transfer from Stellar to an EVM network through LayerZero, from client.usdt0