Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world scope, so the safety profile is covered. The description adds genuine behavioral detail beyond that: the week boundary rule (Mon-Sun, local dates, week containing today) and the per-project grouping. It still omits anything about data freshness, whether zero-hour projects appear, or billed/unbilled treatment.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.