Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover key behavioral traits (read-only, non-destructive, idempotent, closed-world), so the description doesn't need to repeat these. It adds no additional context about what specific contact information is returned, format, or any limitations, but doesn't contradict annotations, so it meets the baseline for having annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.