Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations only say readOnlyHint=false and destructiveHint=false; the description goes beyond that by disclosing parallel fan-out, side-by-side return shape, latency and cost metadata, and the beta-platform $0.00 user charge. It stops short of stating rate limits or model-count constraints explicitly, and doesn't mention that 'models' is mutually exclusive with defaults.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.