mutation IncidentGroupCommentCreate($input: IncidentGroupCommentCreateInput!) {
  incidentGroupCommentCreate(input: $input) {
    errors {
      code
      message
    }
    incidentGroupComment {
      author {
        __typename
        ... on ApiKey {
          __typename
        }
      }
      body
      createdAt
      groupId
      id
      updatedAt
    }
  }
}

{
  "input": {
    "body": "string",
    "incidentGroupId": "value"
  }
}

{
  "data": {
    "incidentGroupCommentCreate": {
      "errors": [
        {
          "code": "RESOURCE_IN_USE",
          "message": "string"
        }
      ],
      "incidentGroupComment": {
        "author": {
          "__typename": "ApiKey"
        },
        "body": "string",
        "createdAt": "value",
        "groupId": "value",
        "id": "value",
        "updatedAt": "value"
      }
    }
  }
}