Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must disclose behavioral traits. It only conveys that it performs an update (a mutation), but gives no information about partial updates, required permissions, reversibility, or effects on related resources. This is insufficient for an agent to know the tool's 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.