Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false. The description adds that it returns specific daily fields and notes the source, but does not disclose additional behavioral details like default date ranges or data update frequency. This adds some value beyond annotations but not rich context.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.