Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral transparency burden. It discloses that chunking and embedding happen synchronously and that the return value is the real chunk count, which is valuable. However, it does not cover error conditions or prerequisites, leaving some gaps.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.