An earlier appointment can still leave care incomplete. (A) The retained RP-01 eye-examination fixture places B-01 at visit/completion ticks 2/5, B-02 at 3/6 and B-03 at 4/7. B-01 lacks interpretation; its candidate endpoint is unavailable. The reference selection rechecks authority, patient acceptability and trust eligibility, reserves B-02, and leaves B-03 as the next choice. Only visit and candidate completion times are supplied; imaging and readout marks indicate availability, not intermediate timing. (B) The proposed execution sequence reserves a stable operation identity, rechecks the current grant, and stops if authority is denied. Unknown receipts remain unresolved; retries query the same identity. A robot additionally requires an independent physical controller, limits, safe stop and escalation. These boundaries establish neither distributed exactly-once effects nor validated physical safety.
