Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden of behavioral disclosure. 'List' implies a read-only operation, and the second sentence clarifies what information the agent should look for. However, it does not describe output format, possible side effects, or any access requirements. This is adequate for a simple listing tool but not richly transparent.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.