Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure. It fails to state side effects (e.g., whether the session is terminated, resources cleaned up), idempotency, or whether it is reversible. The single sentence is insufficient for a state-changing operation.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.