Paint tool in Fusion. Paint mask?

It seems that you can't create paint strokes with the paint node without giving it an input, but unless I'm doing something wrong it seems that makes it useless for doing paint masking? Like if I want to use paint strokes to limit a color correction, or a blur? How do I create strokes without needing to have an input?

Use the MaskPaint node instead.

That's it!

Thanks Bryan.

You can also connect MediaIn -> Paint, do all of your painting on alpha channel and then just swap out the MediaIn with Background generator that has alpha set to 0.0.