Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the description does not need to repeat those traits. It adds useful output context by noting 'ranked matches plus the total count for pagination,' but it does not disclose behavioral nuances like query_embedding overriding sort_by or the default exclusion of unreachable agents, which are left to the schema.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.