Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden but only reveals the output composition, not behavioral traits like whether the call is read-only, premium costs, data latency, or error handling. It does not mention any side effects or access constraints, so the agent lacks safety and expectation-setting context.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.