This script will create joints on every vertex of your curve, if you want your joint to be placed inside your character perfectly, you would definitely draw a 1 degree curve then using point snap you will draw your joints, So here is the script which makes your life much more comfortable. Draw 1 degree curve and adjust the vertex position you like then load your curve on "RM Joint on vertex" window then press Create". That's. I hope you will find it helpful.