Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the transparency burden. It implies a read-only operation via 'Return' and describes the output types, but it does not disclose potential rate limits, data freshness, or whether any API key is required. This is adequate for a simple lookup but minimal.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.