MQTT BIRTH - Setting Ignition Tag Properties

Thanks @jbrzozoski , so “loosely” the syntax would be something like:

{
    "timestamp" : 1465577611580
    "metrics" : [
        {
            "name" : "my_int",
            "value" : 456,
            "type" : "int32",
           *"documentation" : "my documentation"*  <--- new property to add
        }
    ]
}

or is there a special key word that I might be missing? Like:

{
“timestamp” : 1465577611580
“metrics” : [
{
“name” : “my_int”,
“value” : 456,
“type” : “int32”,
“PropertySet” : {
“documentation” : “my documentation”,

}
}
]
}