Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is fully covered structurally. The description adds the nature of returned content (filing dates, direct document links), but says nothing about result ordering, pagination, or rate limits. With annotations doing the heavy lifting, a 3 is appropriate.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.