{"before": {"id": "doubao-seed-2-0-lite-260428", "max_tokens": 500000, "updated_at": "2026-09-18T02:43:18+00:00", "updated_by": 1}, "after_max_tokens": 8192, "reason": "Confirmed upstream 400: max_tokens 500000 exceeds maximum 131072; synthetic test at 8192 succeeded."}