Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so safety is covered. The description adds nothing beyond restating the purpose - it doesn't say what the quality check evaluates, whether the ID must reference an existing perimeter, or what errors occur for missing IDs. With annotations doing the safety work, a 2 reflects that the description contributes no additional behavioral context.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.