Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It usefully discloses that these searches are stored 'locally' (implying a local store rather than a remote call), which is real behavioral context. However, it says nothing about read-only semantics, permissions, or failure modes when no saved searches exist.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.