Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full behavioral burden. It clearly indicates that the tool returns metadata rather than content, implying a read-only listing. It does not disclose output format, failure behavior, or side effects, but for a simple list operation this is minimally acceptable.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.