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. 'Get task status' implies a read-only operation, but it doesn't specify whether this requires authentication, what permissions are needed, whether there are rate limits, what the response format looks like, or whether this is a real-time status check versus historical data. The description provides minimal behavioral context beyond the basic operation.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.