Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of disclosing behavior. It adds useful context that the feed is a sample, is limited to public videos, and is ordered by newest. However, it does not disclose pagination behavior, defaults, authentication needs, or what happens when cursor vs. page is used.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.