Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure. It states the core action but does not mention side effects, whether the layer must already exist, whether the change is reversible, or whether other layer properties (like lock state) are unaffected. The description adds little beyond the direct action.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.