Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior. The description adds value by detailing what headers are inspected, what issues are flagged (e.g., unsafe-inline, weak X-Frame-Options), and detection of CDN/WAF interception. No contradictions.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.