Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, destructiveHint=false, idempotentHint=false, openWorldHint=false. The description adds no behavioral context beyond 'create' – it doesn't mention whether creating a scene with an existing name fails or overwrites, whether it affects the current scene, or any side effects. With annotations covering the safety profile, a 3 is appropriate – the description adds minimal behavioral context but doesn't contradict annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.