Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already flag destructiveHint=true and readOnlyHint=false, so the bar is lower, yet the description still adds real value: the side effect that every paired screen stops showing the dashboard, the hard restriction on Home, and the requirement to confirm with the person first. It does not state permission requirements or reversibility, but the disclosed blast radius goes well beyond the annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.