Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already provide readOnlyHint=true, destructiveHint=false, idempotentHint=true, and openWorldHint=true, which fully cover safety and idempotency. The description adds no behavioral context beyond what annotations declare—it doesn't mention response format, pagination, rate limits, or authentication requirements. However, it doesn't contradict annotations, so it meets the lower bar with annotations present but adds minimal value.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.