Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds meaningful behavioral context by specifying that the output is grouped into owned brand mentions, competitor signals, demand signals, and conversations, which is more than the annotations provide. It does not mention pagination or rate limits, but for a read-only summary tool this is acceptable.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.