Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is fully covered. The description adds only the constraint that the asset must already exist; it says nothing about auth needs, error behavior for unknown ids, or pagination. With annotations carrying the load, this is adequate but thin.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.