GraphQL Node fails with "Could not get input with given index"

Describe the problem/error/question

Hello,

I’m running a GraphQL node and face some interesting behavior. Lets say I have three requests executed. If all requests fail, the node returns a valid response like this here (this was with two requests):

[
  {
    "errors": [
      {
        "message": "6 is not a valid NullText",
        "path": [
          "createPropressale"
        ],
        "extensions": {
          "code": 400,
          "errors": []
        }
      }
    ],
    "data": null
  },
  {
    "json": {
...
    },
    "pairedItem": {
      "item": 0
    }
  },
  {
    "json": {
...
    },
    "pairedItem": {
      "item": 1
    }
  },
  {
    "errors": [
      {
        "message": "9 is not a valid NullText",
        "path": [
          "createPropressale"
        ],
        "extensions": {
          "code": 400,
          "errors": []
        }
      }
    ],
    "data": null
  },
  {
    "$error": {
      "message": "9 is not a valid NullText",
      "timestamp": 1744264087818,
      "name": "NodeApiError",
      "description": null,
      "context": {}
    },
    "itemIndex": 1
  }
]

But as soon as I add another successful request, the node does not give me any valid output anymore:

So that happens when in the batch there are:

  • failing requests > 1
  • successful requests > 0

1 failing and 1 successful works. All failing works. All successful works.

Information on your n8n setup

  • n8n version: 1.67.1
  • Database (default: SQLite): Postgres
  • n8n EXECUTIONS_PROCESS setting (default: own, main): main
  • Running n8n via (Docker, npm, n8n cloud, desktop app): Docker
  • Operating system: Ubuntu 24