Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations (readOnlyHint, idempotentHint, destructiveHint) already indicate a safe, read-only operation. The description adds that it searches by specific fields but does not disclose pagination, rate limits, or response behavior. It meets a baseline but adds minimal extra value.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.