Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly, idempotent, non-destructive and a closed world, so safety is covered. The description adds genuinely useful substance beyond them: the 0-100 scale, the four constituent factors with parenthetical definitions, and the fact that it concerns forward-guidance trustworthiness. It does not discuss data freshness or coverage limits, keeping it 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.