Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral transparency burden. It discloses what the tool returns (field metadata including keys, labels, types, requiredness, help text, and options) and implies a read-only metadata lookup. But it does not mention side effects, authentication needs, rate limits, or error behavior, leaving some behavioral context unstated.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.