Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds significant behavioral context beyond the annotations: it explains the conditional response when all providers are connected (authenticated:true, empty pending[]) and when credentials are missing (returns connect_url and per-install URLs). This transparently describes what the tool returns in different states, which is exactly what an agent needs. Annotations are consistent, with no contradiction.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.