Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden of behavioral disclosure. It states that the tool creates a surface, names the underlying Rhino command, and documents the return dictionary, which is useful. It does not discuss what happens in the active Rhino document, coordinate-system assumptions, or failure behavior, so it is adequate but not rich.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.