Monitor USDT Transaction

Begin tracking a USDT transaction.

Once monitoring is started, our system will send HTTP callbacks to your configured endpoint whenever the transaction status changes. The callback format and delivery rules follow the same pattern as described in the Callback Notification documentation.

About testnet

• Accepts only numeric values (0 or 1).
• 0 = mainnet, 1 = sepolia testnet.
• Defaults to 0 (mainnet) if omitted.

About status in callbacks For USDT transactions, the status integer in the callback payload reflects the exact blockchain confirmation count at the time the callback is sent. Callbacks are only sent when the status changes to one of the following values:

• -1 = Reverted (failed or dropped from mempool)
• 0 = Exactly 0 confirmations (unconfirmed)
• 1 = Exactly 1 confirmation
• 2 = Exactly 2 confirmations — this is the final status reported by our system. We do not send callbacks for 3 or more confirmations. If you require tracking beyond 2 confirmations, you must query the blockchain directly.

Other callback fields include:

• addr: Receiving address
• value: Payment amount in the smallest unit (for USDT, in token base units)
• txid: Transaction hash