Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare destructiveHint true and idempotentHint true, so the safety profile is known. The description adds that it clears 'sensitive data the agent saved earlier,' which is useful, but it does not disclose edge cases like what happens if the key does not exist. No contradiction with annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.