Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of disclosing behavior. It merely states 'Delete a conversation' without mentioning irreversibility, cascading effects on related data (e.g., messages), permissions, or any side effects. This is insufficient for a destructive operation.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.