Sell
transaction_status values sent: COMPLETED, FAILED, REFUND_COMPLETED
Pool Sell
transaction_status values sent: COMPLETED, FAILED, REFUND_COMPLETED. Same body as Sell; event is SELL.
External Sell
status values sent, in order: FUNDS_RECEIVED → PAYMENT_INITIATED → COMPLETED.
Failure path: REFUND_INITIATED, REFUND_FAILED, REFUND_COMPLETED (always followed by a FAILED webhook), FAILED.
refund_transaction_hash is also included.