Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure. It only states 'Edit a scheduled event' and 'fields = raw Discord event fields' without explaining effects (e.g., whether editing a started event is allowed, if changes are immediate, or if there are any rate limits or side effects).
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.