Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden, and it delivers the single most important trait: idempotency ('幂等:未运行时也正常返回' — returns normally even when not running). It does not say what happens to in-flight chats/requests or whether authentication is required, but the idempotency disclosure is genuine non-obvious behavior beyond structured fields.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.