If you INSIST on using a cutting agent/diluent, use triethyl citrate… there is evidence to suggest that it is substantially safer than the other cutting agents/diluents (Making carts - #49 by awkwardballer).
Like everyone else has said, if you choose the right hardware, you don’t need to use cutting agents. All you need is distillate (90-97%) and terpenes (3%-10%)
AVD pens are example of “right hardware”: https://avd710.com/