Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations confirm the tool is read-only, idempotent, and non-destructive, so the description does not need to cover safety. It does not add extra behavioral context such as caching behavior (partially covered by the force_refresh parameter schema) or what the audit reports. With annotations covering the core traits and an output schema presumably describing results, a baseline 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.