Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond the structured annotations (readOnlyHint=false, destructiveHint=false, idempotentHint=true), the description adds no additional behavioral context. It does not disclose what happens to the session after stopping, whether it can be restarted, whether resources are released, or what the return value is. The 'active' qualifier is a mild pointer but not explicit about behavior for already-stopped sessions.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.