Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare destructiveHint=true, readOnlyHint=false, openWorldHint=true, and idempotentHint=false, so the safety profile is covered. The description adds nothing beyond these — it does not disclose side effects, required permissions, what gets created, or the non-idempotent nature (which annotations already cover). With annotations doing the heavy lifting, the description's contribution is essentially zero.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.