{
  "case_id": "HX-S01",
  "grid": "fine",
  "checkpoint": "Last written field at pseudo-iteration 275; solver log reached 279 before interruption.",
  "status": "Partial diagnostic; not a 1000-iteration result and not part of the frozen baseline acceptance score.",
  "metrics_at_checkpoint": {
    "hot_heat_duty_W": 7.265789,
    "cold_heat_duty_W": 7.416673,
    "hot_pressure_drop_Pa": 1799.575,
    "cold_pressure_drop_Pa": 1807.188,
    "mass_imbalance_percent": 0.06227,
    "energy_imbalance_percent": 2.034
  },
  "interpretation": "No 1000 residual result or medium-to-fine continuation comparison is available. Do not treat this checkpoint as convergence."
}