Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations present, the description shoulders the behavioral burden. It explicitly states 'read-only,' which communicates that no mutation occurs. However, it does not describe return format, ordering, or behavior when a location has no assigned menu, though this is a minor gap for such a simple list operation.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.