Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden. It discloses the nature of the data (current pricing, in USD, monthly vs one-time) and adequately conveys that this is a read-only informational tool. However, it does not mention potential staleness or whether the data is dynamic.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.