Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full behavioral disclosure burden, and 'read-only' clearly signals a non-mutating operation. It does not describe output format or privileges, but for a zero-parameter inspection tool the key safety-relevant behavior is stated.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.