from mojo.events import EditingTool, installTool

class MyTool(EditingTool):
    def __init__(self):
        super().__init__()
        self.specialPoints = [] # My Custom Attribute

This attribute will contain set of points that should be selected by a user.
At some point this class adds selected points to this list

def additionContextualMenuItems(self):
    return [("Create Special Point", self.createSpecialPoint)]

def createSpecialPoint(self, sender):
    g = CurrentGlyph()
    for p in g.selection:
        self.specialPoints.append(p)

Is there any way to track this action, so If the user will use Undo/Redo, the points will be deleted form the list or re-added to the list in the right order? Also this Undo/Redo should still track other actions of course.

I think I should use didUndo(), but how?

I was thinking of tracking changes by adding the labels, but changes in the labels are not tracked by history related events.

Thanks in advance for the help!

glyph.prepareUndo("Moved By 100, 100")
glyph.moveBy((100, 100)
glyph.performUndo()

see RGlyph.performUndo

in the next release (RF3.2) you can use:

with glyph.Undo("Moved By 100, 100")
    glyph.moveBy((100, 100)

good luck!