Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description nevertheless adds important provenance context: the practice questions are aitrainer.work's own and not a platform's real interview questions, which matters for how an agent presents the output. It says little about how the two optional inputs combine or what happens when one is omitted.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.