mutation MarkWelcomeChecklistItem($input: MarkWelcomeChecklistItemInput!) {
  markWelcomeChecklistItem(input: $input) {
    clientMutationId
    completed
    errors
    totalCompletedCount
    totalCount
  }
}

{
  "input": {
    "completed": true,
    "targetId": "id",
    "targetType": "CLUSTER"
  }
}

{
  "data": {
    "markWelcomeChecklistItem": {
      "clientMutationId": "string",
      "completed": true,
      "errors": [
        "string"
      ],
      "totalCompletedCount": 1,
      "totalCount": 1
    }
  }
}