Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry full behavioral disclosure. It reveals that this is a GUI engine v2 live-preview operation, which is useful context, but it omits whether the GUI must be running, whether the action is reversible, what happens with an invalid layer index, or any side effects on the current view.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.