Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden, and it delivers: it details what is returned (list vs dict), what is not returned (HTML content), the token-saving behavior, and specific error conditions (ValueError for path escape, missing file, or missing metadata). This is thorough and goes beyond the bare minimum.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.