Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, so the safety profile is covered by structured data. The description adds two useful behavioral nuggets beyond that: tasks are 'persisted' (i.e., stored records, not ephemeral/in-memory state) and results are scoped to the current user, implying an authentication-derived filter. It does not describe ordering, pagination, or volume limits.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.