Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral burden. It usefully discloses a flat cost of 5 points per successful run and lists the returned profile contents, but it omits auth/permission requirements, rate limits, and any other operational constraints.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.