Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, destructiveHint=false, idempotentHint=false and openWorldHint=true, so the safety profile is covered, but the description adds nothing: it does not say what payload a 'batch action' requires, whether partial failures are tolerated, or whether the effect is reversible. For a non-idempotent mutation the phrase 'batch action on multiple objects' conveys almost no behavioral information.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.