Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety and network-access profile is covered. The description adds genuine value by naming the return fields, but says nothing about result limits or pagination, which matters for an open-world account-level listing.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.