Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, destuctiveHint=false, idempotentHint=true, and openWorldHint=true, covering safety and idempotency. The description adds that the tool returns message IDs, which is useful. No contradictions. Missing details like rate limits or authentication needs, but annotations compensate.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.