Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are supplied, so the description carries the full burden. It discloses the server-side SHA-256 hash computation, the need for a payer-signed locker:write envelope, the two-phase keyless envelope spec flow, the request-path streaming for synchronous confirms of large objects, and the async finalize job with terminal statuses (complete, partial, failed).
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.