Hi @techrahul95 ,
You can put whatever you’d like into the payload of the message. You would just have to make sure the consumers know what to expect so they can properly parse it.
But I would caution against not using user-defined properties just b/c the try-me tool doesn’t allow you to do so. In many cases it makes a lot of sense to use user-defined properties as they can allow the consumers to know context about the message they are receiving. Things like an ApplicationMessageID, OrderID, type information, etc. are very common