Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already establish the safety profile (readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint=false), so the description earns credit for what it adds: the concrete shape of each returned entry and the side-signal that it also reports whether AI is configured on the server at all. That last clause matters behaviorally — a caller can learn AI is unavailable without a failed run — and is not derivable from any structured field.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.