Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false, and destructiveHint=false, so the safety profile is covered externally. The description adds nothing beyond that — no note on what the returned details include, whether the conversation may be missing, or error behavior. With annotations carrying the load, the description still contributes almost no extra context.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.