Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. 'Lists' clearly signals a read-only operation, and 'managed and discovered' plus 'current Workspace' add useful scoping context. It could further disclose ordering, pagination, or return shape, but for a zero-parameter listing operation the behavior is transparent enough.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.