Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations available, the description carries the burden of conveying behavior. The verb 'List' signals a non-destructive read operation, which is helpful. However, it does not disclose what the response contains, whether empty results are possible, or any service state requirements, leaving some behavior unexplained.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.