Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations only declare readOnlyHint=false and destructiveHint=false; the description adds nothing about what revoking does (access termination, reversibility, notification, whether the subscription record is deleted) or about batch failure behavior. For a mutation that revokes subscriptions across up to 500 users, this leaves the effect semantics entirely unspecified.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.