Polyline segement - delete the point where line joins

For my diagrams, user is able to create line with multiple segement ( The example of DirectLink you provided previsouly)
by using the center adjustment handle of line.

What those adjustment handles are called ?

And how one can delete same using context menu (when clicked ??)
OR on mouse over, show some small button next to those point and when clicked delete that point from line segement and make a straight line between the other two ends of that point.

This describes the LinkReshapingTool: GoJS Tools -- Northwoods Software.

I’m not sure if you are referring to the reshaping handles or the resegmenting handles.

Using a context menu is possible but would have to be implemented. Few people do that any more because automatic resegmenting seems easier for most cases.