There are disjointed toolsets all over the place..." or "There are disjoint toolsets all over the place

There are disjointed toolsets all over the place..." or "There are
disjoint toolsets all over the place

I have only ever heard the expression "There are disjoint sets" and never
"There are disjointed sets"
I believe it should be "disjoint sets" but I don't have a good reason why.
Thanks in advance, Martin