Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description does not need to restate that. It adds meaningful behavior beyond the annotations: every result is a cited public record, and visibility is applied before text is searched or excerpted, which is important context for an agent using public search.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.