Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The annotations already declare destructiveHint=true, and readOnlyHint=false, so the agent knows it's destructive. The description adds context by stating the deletion purpose and the kind of data (memories, sensitive data), which goes beyond the annotations. It doesn't mention irreversibility or missing-key behavior, but the idempotentHint covers safety.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.