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 one genuinely useful behavioral trait: the result ordering (v2 newest first, then v1). However it says nothing about permissions, whether the list is exhaustive or paginated, or what a token record contains.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.