Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate this is a non-read-only, non-idempotent, non-destructive mutation, so there is no contradiction. The description adds the useful precondition that the upload must already have happened, but it does not disclose what state changes occur, whether repeated calls fail, or what downstream effects completion triggers.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.