Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare the tool as readOnlyHint, idempotentHint, and non-destructive, so the description doesn't need to repeat safety traits. It adds value by listing typical returned fields (model, serial, firmware), giving the agent a concrete sense of output. No contradictions with annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.