Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden but only states the action ('Update') without disclosing behavioral traits like permissions required, whether changes are reversible, rate limits, or response format. It lacks critical context for a mutation tool, making it insufficient for safe use.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.