Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already communicate that this is mutating, idempotent, and non-destructive, so the description's job is lighter. It adds the contextual effect of returning documents to the system, but it does not describe edge cases such as restoring a document that is not in the trash, whether metadata is preserved, or what the API returns.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.