Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. 'List' clearly implies a read-only, non-destructive operation, and the 'active' qualifier tells the agent which sessions are included. However, it omits any statements about side effects (e.g., that no sessions are modified) or potential authentication/context requirements, though for a listing tool these are largely implicit.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.