Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered elsewhere. The description adds nothing about pagination, default result limits, or filtering behavior — the useful behavioral facts for a list endpoint — beyond a pointer to describe_operation.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.