Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint and idempotentHint true, covering the safety profile. The description adds useful context by listing the returned fields and noting 'Free,' but does not discuss authentication, rate limits, or the exact format of the PaymentRequired document. With the annotations carrying the main behavioral burden, a 3 is appropriate.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.