Confirm the pending Pro task's complete instrument list and rhythm/paper options. instruments=null permits unconstrained supplier part identification. The metered flow holds a price confirmation before starting; exempt processing requires explicit start authorization. Identical confirmations reuse the task. pro_options support source-established time_signature, fixed/followed tempo, performance/quantized timing, subdivision and page size; omission uses N/4 and does not detect compound meter. Null instruments select automatic parts, included in the same quote/start consent. replay_only requires an exact saved result and cannot create a supplier job.