The audit trail records every action's full life: the source records the AI read, the draft it prepared, its reasoning and risk level, every edit, the human decision (approved, declined, reassigned) with who and when, and the exact result the target tool returned. Declined actions are kept too; judgment exercised is part of the record.
What it is for, practically: ending disputes ("the reminder cited invoice #1082 and was approved by Sam on March 4 at 9:12"), onboarding ("read last week's trail to see how we handle these"), oversight (viewers can inspect everything without approval rights), and self-calibration: filtering the trail by edited and declined actions shows you exactly where the AI still needs your judgment.
Everything is timestamped and attributed, nothing that executed is deletable from the record, and access follows roles. If your accountant or a partner asks "what does the AI actually do," the honest answer is: here is the log, every line of it.