Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already establish readOnly, idempotent, non-destructive, closed-world behavior, so the safety bar is met structurally. The description adds a genuinely useful behavioral fact beyond them: the OpenRouter key itself is never returned, only its connection status — important for an agent reasoning about secrets. It stops short of noting auth/permission requirements.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.