Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. It does disclose the return format (markdown) and that the whole page is returned ('full text'), which implicitly addresses truncation, but it says nothing about auth requirements, error behavior for an unknown path, or whether boilerplate/navigation is included.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.