Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry the full burden of behavioral disclosure. It only states 'delete' but omits critical traits such as whether the operation is irreversible, whether cascading deletion occurs (e.g., sessions, messages), permission requirements, or async behavior. This is insufficient for a destructive tool.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.