[
  {
    "op": "core/column-addition",
    "engineConfig": {
      "facets": [],
      "mode": "row-based"
    },
    "baseColumnName": "M|519",
    "expression": "grel:value",
    "onError": "set-to-blank",
    "newColumnName": "4204",
    "columnInsertIndex": 3,
    "description": "Create column 4204"
  }
]