Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
There are no annotations, so the description carries the full burden. It reveals the scope ('across all enrolled courses') but does not clarify expected behavior such as whether it aggregates by course, whether it is read-only, or what the return structure looks like. For a simple lookup tool this is partially acceptable, but the absence of any behavioral detail is a gap.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.