put https://yourServer.jamfcloud.com/JSSResource/webhooks/id/
The display_fields are only applicable to the SmartGroupMobileDeviceMembershipChange event. Accepted values (capitlization sensitive) are the same as those available from the GUI when making and Advanced Search. display_field_additions can be used in place of the display_fields element to append new fields to an existing webhook.
Sample Request Body
Below is an example request body that can be used to update the display fields returned in a webhook response body whose event type is SmartGroupMobileDeviceMembershipChange. A default set of attributes are pre-configured when enabling this functionality and cannot be removed from the response. Accepted values (case sensitive) are the same as those available from the GUI when making an Advanced Search.
<webhook>
    <name>Sample</name>
    <enabled>true</enabled>
    <url>https://server.com</url>
    <content_type>application/json</content_type>
    <event>PatchSoftwareTitleUpdated</event>
    <connection_timeout>5</connection_timeout>
    <read_timeout>2</read_timeout>
    <authentication_type>NONE</authentication_type>
    <username/>
    <password/>
</webhook><webhook>
    <enable_display_fields_for_group_object>true</enable_display_fields_for_group_object>
    <display_fields>
    	<display_field>
        <name>IP Address</name>
      </display_field>
    	<display_field>
        <name>Last Enrollment</name>
      </display_field>
    </display_fields>
</webhook>