Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and external-data traits are covered. The description adds that the content is 'fresh' and comes from a 'public feed', implying live, unauthenticated data, which is modest extra context but no pagination, freshness window, or ordering details.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.