I don't think it's possible imo it works that way:
Client sends req to server that some1 is tryin a craft, server rolls a dice and options are:
- fail
- +0 worst
- +0 better
- +1
- +2
- +3
And than after it rolls which one will be made, that is send back to client to show what you have made...
But I can't asure you that it works this way, it's just my opinion and how I would do it.