Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already define read-only, open-world, and idempotent behavior. The description adds meaningful context: it returns full per-agent scoring data plus comparison context, and notably reveals that the tool does not declare a universal winner — showing evidence differences. This goes beyond the annotations and helps the agent interpret results.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.