Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is clear. The description adds valuable behavioral context beyond annotations, such as the role-based response differences (bilingual vs. single locale) and the default time window.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.