Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden of disclosing effects. It states the side effect (removal from the index) and the non-effect (the PDF remains), which is genuinely useful. It does not mention reversibility, errors, or return behavior, but the operation is simple enough that this is a minor gap.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.