Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly, idempotent, and non-destructive behavior. The description adds 'Prefers Explorer decoded receipt data,' which gives context about data sourcing but does not detail behavior when Explorer data is unavailable. This adds marginal value over annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.