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 clear. The description adds meaningful behavioral context beyond annotations by explaining that the response includes a source_url pointing to the National Law Information Center and instructing that this link must be presented when citing cases. This is useful operational guidance not present in the structured fields.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.