Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden; 'Get' implies a read-only call, and it does disclose what content is returned (runtime and economics parameters), which is real behavioral value. It stops short of stating idempotency, caching, or whether the config is a static snapshot, leaving gaps a zero-annotation tool must otherwise cover.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.