Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden, but 'Show' clearly signals a non-mutating read and the enumerated outputs (state, capabilities, queued events, PID) tell the agent what information it yields. It does not clarify whether calling it has side effects on queued events, or whether it requires an active connection.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.