A backup you've never tested restoring isn't really a backup — it's a hope. The File Registry and Restore Planner exist to close that gap.
Register the config files that actually matter for a service — the ones that, if lost, would mean rebuilding from memory instead of from a copy. Each registered file tracks its own backup and restore history, with a trust state: has this specific file actually been verified restorable, or has it just been sitting there since it was registered?
When you actually need to restore something, the Restore Planner doesn't just hand you a file and wish you luck:
A backup job reporting success tells you the copy step worked. It doesn't tell you the copy is actually usable, that you know how to restore it under pressure, or that restoring it won't break something else it depends on. The Restore Planner is built around that distinction — see also the Recovery Score on each service's dashboard card, which is driven by the same trust data.