curl --request POST \
  --url https://www.zohoapis.com/writer/api/v1/documents/a1b2c3d4e5f6g7h8i9/merge \
  --header 'Authorization: Zoho-oauthtoken d92d4xxxxxxxxxxxxx15f52' \
  --header 'content-type: multipart/form-data' \
  -F 'output_settings={
  "format": "pdf"
}' \
  -F 'merge_data={
  "data": [
    {
      "customer_name": "John Miller",
      "customer_email_address": "john.miller@zylker.com",
      "invoice_number": "INV-2026-045",
      "items": [
        {
          "items.item_code": "SKU-1001",
          "items.item_name": "Aria Smartwatch S2",
          "items.item_images": [
            "https://workdrive.zoho.com/external/sample-image-id-1/download?directDownload=True",
            "https://workdrive.zoho.com/external/sample-image-id-2/download?directDownload=True"
          ],
          "items.item_replacement": "Yes"
        }
      ]
    }
  ]
}' \
  -F 'merge_data_csv_content=@file_path' \
  -F 'merge_data_json_content=@file_path' \
  -F 'merge_data_csv_url=https://zylker.com/merge-data.csv' \
  -F 'merge_data_json_url=https://zylker.com/merge-data.json' \
  -F 'record_id=4876000000123456' \
  -F 'response_type=link' \
  -F 'filename=invoice_john_doe' \
  -F 'sign_service_name=docusign' \
  -F 'test_mode=true'

    headersMap = Map();
    headersMap.put("Accept", "application/json");

    list_of_text=List();
    list_of_text.add({"paramName":"output_settings","content":"[object Object]","stringPart":"true"});
    list_of_text.add({"paramName":"merge_data","content":"[object Object]","stringPart":"true"});
    file=invokeurl
    [
      url : "public fileURL link"
      type : GET
    ];
    list_of_text.add({"paramName":"merge_data_csv_content","content":file,"stringPart":"false"});
    file_2=invokeurl
    [
      url : "public fileURL link"
      type : GET
    ];
    list_of_text.add({"paramName":"merge_data_json_content","content":file_2,"stringPart":"false"});
    list_of_text.add({"paramName":"merge_data_csv_url","content":"https://zylker.com/merge-data.csv","stringPart":"true"});
    list_of_text.add({"paramName":"merge_data_json_url","content":"https://zylker.com/merge-data.json","stringPart":"true"});
    list_of_text.add({"paramName":"record_id","content":"4876000000123456","stringPart":"true"});
    list_of_text.add({"paramName":"response_type","content":"link","stringPart":"true"});
    list_of_text.add({"paramName":"filename","content":"invoice_john_doe","stringPart":"true"});
    list_of_text.add({"paramName":"sign_service_name","content":"docusign","stringPart":"true"});
    list_of_text.add({"paramName":"test_mode","content":"true","stringPart":"true"});

    response = invokeUrl
    [
        url: "https://www.zohoapis.com/writer/api/v1/documents/{document_id}/merge"
        type: POST
        headers: headersMap
        files: list_of_text
        connection: connection_name
    ]

    info response;