Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already establish read-only, idempotent, non-destructive, closed-world behavior, so the safety bar is low. The description adds genuinely new behavioral context: the query matches session text or memory content/id, and project matching is case-insensitive. It does not describe result ordering or how sessions and memories are merged in the result set.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.