Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure. It mentions 'replace' and 'rebuild blob' which imply mutation, but does not state side effects, safety, reversibility, or whether the operation is in-place or produces a new file (output parameter exists but is not described).
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.