Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly, idempotent, and non-destructive, so the safety profile is covered. The description adds genuinely useful non-annotation behavior: the expected poll cadence, the 3-minute bound, and that structured completion carries compact reportSummary evidence once the stored report is ready.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.