Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It discloses that variables are global, can be deleted with None, and input_dialog prompts operators. However, it does not mention side effects, permissions, or the nature of the return message (beyond 'operation result message'). This is adequate but not comprehensive.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.