Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is fully covered without the description. The description adds nothing behavioral beyond that — no return format, no pagination, no ordering — so it does not earn credit above the annotation floor.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.