<Route Url="/json/addperson" Method="POST" Call="DATA.SomeClass:SomeMethod"/>

{
    "Id":6508,
    "Name":"",
    "Subjects" : [
    {
        "Title" : "blahblah",
        "Number" : 3
    },
    {
        "Title" : "blahblahblah",
        "Number" : 6
    } 
    ]
}

ClassMethod SomeMethod() As %Status
{
  do ##class(%ZEN.Auxiliary.jsonProvider).%ConvertJSONToObject(%request.Content,,.data,1)
}

for i=1:1:data.Subjects.Count()
{
   set subject = data.Subjects.GetAt(i)
}