txn_*) is one money movement recorded from your party’s point of view. Every Payment and Transfer that touches your party produces one, so the transaction list is the single feed to reconcile against. Transactions are read-only: you create payments and transfers.
Reading a transaction
Each transaction says what kind of movement it was, which direction the money went relative to you, and which payment or transfer produced it. Movements that settle asynchronously, like ACH deposits, carry a projected funds-available time.sourcePartyId identifies the party money leaves, not the party whose credentials initiated the
request. For a payment made on a customer’s behalf it is the customer. An external deposit has no
Natural source party, so sourcePartyId is null and destinationPartyId is the customer. Use the
transaction direction and both party fields together; do not substitute the acting developer or
agent for the source of funds.