Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly, idempotent, and non-destructive behavior; the description adds only the 'agent-native mandate rails' context, which is vague and does not disclose processing details, error behavior, or permission nuances. No contradiction with annotations, but minimal additional value beyond them.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.