Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations available, the description carries the full burden. It discloses the data source, public domain status, no key requirement, and update frequency (updated daily), which is good behavioral context. It also lists the return components, giving a sense of the response shape without an output schema.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.