Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must fully convey behavioral traits. It only states a fetch operation, but does not disclose whether it is read-only, requires authentication, or any side effects. The presence of an output schema partially compensates, but the description itself is insufficient.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.