Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover read-only, idempotent, non-destructive, closed-world behavior, so the bar is lower. The description still adds real context annotation cannot: every fact is dated, 'claimed' and 'found' are kept apart, and the record distinguishes vendor claims from INITE-measured findings. It does not discuss error behavior for unknown tools or rate limits, so it stops short of a 5.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.