Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. It discloses the key side effect (wind-down of positions) and states the return shape (success or error), which is meaningful. It does not mention irreversibility, permissions, or ordering constraints, but the main behavioral trait is covered.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.