Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of behavioral disclosure. It only states the action ('check validity') without detailing what 'validity' entails (e.g., topological correctness, coordinate constraints), potential side effects, error handling, or output format. This leaves significant gaps in understanding the tool's behavior beyond the basic purpose.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.