Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds non-obvious behavioral context: popularity is based on AI assistants actually fetching the articles, not generic view counts or editorial picks.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.