Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The annotations already establish read-only, idempotent, non-destructive behavior. The description adds meaningful context by disclosing the $0.25 USDC cost and the response shape with 5 fields including `exception` and `field`, which helps the agent understand the paid-call and output characteristics.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.