Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden. It discloses that the tool retrieves details including messages and entities, implying a read-only operation. However, it does not mention error behavior, permissions, or side effects. It adds some value beyond the schema but lacks depth.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.