Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations present, the description carries the burden of behavioral disclosure. It communicates that the operation lists quests and supports optional filters, but it does not state defaults (e.g., which status is used by default), pagination, ordering, or what the response contains.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.