Journal
What was decided and why, with a Support reference on every entry.
What the risk engine and the order path did, kept so that an event can be explained afterwards - by you reading it, or by support. Every entry carries a Support reference like PC-4K2M9X.

What is in it
Orders placed, refused and filled; modifications; Breaches, Locks and Auto-flattens; rule edits; connection events. A refusal records the reason the engine gave, in the numbers it gave, rather than a summary of it.
Support references
One per risk or order event, minted when the event happens and attached to the trade for good. It is the safe handle: raw broker ids never reach the UI, so a reference is what you quote in a ticket and what support looks up.
Retention
Journal entries are kept for 730 days and then swept. What is exported when you ask for your data includes them.