Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description is the sole source of behavioral disclosure. It does reveal that omitting the argument lists available methods, but it doesn't state whether the operation is read-only, if it has side effects, or what happens for invalid names. This falls short of full transparency.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.