On-init reference number

Hi @IntegrationSupport, I have a doubt in On-init APIs where this reference number is coming from can you help me with this?
{

"requestId": {{$guid}},

"timestamp": {{$isoTimestamp}},

"transactionId": "",

"link": {

    **"referenceNumber": "VISIT:7e9f17d6-2963-49dc-b41c-5d31cd1525dd",**

    "authenticationType": "DIRECT",

    "meta": {

        "communicationMedium": "MOBILE",

        "communicationHint": "string",

        "communicationExpiry": {{$randomDateFuture}}

    }

},

"error": null,

"resp": {

    "requestId": "076a808d-54da-4b27-939f-0e68064a5ec5"

}

}

@Abishekbv Reference number is the care context number of a patient. And this need to be unique. You can refer to Webinar 8 also. https://sandbox.abdm.gov.in/webinars