Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry behavioral context; it helpfully discloses that counts are real and include zeros, and that AI visits are scoped to the last 30 days by client. However, it does not state read-only behavior, whether results are cached or sampled, or what the response structure looks like.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.