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 the meaningful behavior: the call returns freshly generated (non-deterministic) tasks, each self-describing its rules and answer_shape, and it imposes the constraint that the caller must solve them itself. It does not mention auth requirements, whether prior task sets are invalidated, or any rate limits.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.