Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare this as read-only, idempotent, non-destructive, and closed-world, so the description has a lower disclosure burden. It adds useful behavioral context by saying the result is a structured protocol returned as Markdown and HTML ready to fill in or print, without contradicting the annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.