Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations only indicate non-read-only, non-destructive behavior. The description adds useful context by stating that it saves current work and creates a full timestamped database backup, implying persistence and uniqueness. It does not detail backup location or completion behavior, but for a zero-parameter tool this is reasonably transparent.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.