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 covered without the description. The description adds nothing at all — no note on whether the object is scoped to a folder/perimeter, what authorization is needed, or what happens on a missing id — so the lower bar for annotated tools is only barely met.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.