Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden, and it under-delivers: it never mentions that clicks may navigate away from the page, that writes are gated, or that allow_writes (default false) governs whether this action is permitted. For a potentially state-changing browser automation tool, the safety-relevant behavior is undisclosed.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.