Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already signal that this is a non-read-only, non-idempotent mutation, so the description does not need to repeat those hints. It adds the useful sequencing context that the upload must already have happened, but it does not disclose what 'complete' does to the capture (e.g., status transition, validation, irreversibility).
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.