Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden, and it does disclose two real behavioral traits: results are ordered newest first, and the call has two distinct modes depending on whether host is supplied. It stops short of stating that this is a read-only operation, whether any pagination or limits apply, or what authentication is needed.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.