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. It discloses that the token is validated, cached for subsequent calls, and never echoed. This gives useful operational transparency about session state and privacy, though it doesn't mention error handling or what happens on invalid tokens.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.