mutation UpdateCustomField($input: UpdateCustomFieldInput!) {
  updateCustomField(input: $input) {
    clientMutationId
    customField {
      allowAdHoc
      answers {
        edges {
          __typename
        }
        nodes {
          __typename
        }
        pageInfo {
          __typename
        }
      }
      createdAt
      description
      id
      maxCharacters
    }
    errors
  }
}

{
  "input": {
    "id": "id"
  }
}

{
  "data": {
    "updateCustomField": {
      "clientMutationId": "string",
      "customField": {
        "allowAdHoc": true,
        "answers": {
          "edges": [
            {
              "__typename": "CustomFieldAnswerEdge"
            }
          ],
          "nodes": [
            {
              "__typename": "CustomFieldAnswer"
            }
          ],
          "pageInfo": {
            "__typename": "PageInfo"
          }
        },
        "createdAt": "value",
        "description": "string",
        "id": "id",
        "maxCharacters": 1
      },
      "errors": [
        "string"
      ]
    }
  }
}