Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry the behavioral burden, but it only states the abstract push/pull action and signed distance. It does not disclose that this is a mutating edit, that geometry is changed in place, whether it is reversible, or what input selection state is required.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.