Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint and a closed-world, non-destructive profile, so safety is covered. The description adds genuinely non-obvious behavior: matching is keyword/full-text rather than semantic, results are scoped to a single project, and only the latest version of each memory is returned (superseded versions are excluded). It omits ranking/ordering and truncation behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.