Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry the burden of behavioral disclosure. It discloses the 'Live' nature (real-time API call) and the config requirement (setup/auth context). However, it does not explicitly state read-only behavior, potential side effects, or any rate limits. This is a partial disclosure, hence a 3.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.