Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate read-only, idempotent, non-destructive behavior. The description adds significant behavioral detail by specifying the exact output conditions (authenticated vs. missing credentials) and the URLs returned. It describes side effects (none) implicitly. This exceeds the annotation coverage but doesn't cover edge cases like partial connectivity. Score 4.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.