Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered by structured data. The description adds that results carry mapping confidence, which is useful behavioral context, but says nothing about unmatched values, fallback behavior, or open-world lookup implications.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.