Quad Adder is a modeling tool that simplifies the process of generating new quad faces along open mesh boundaries. It is particularly useful for constructing or repairing curved surfaces. The operator allows you to select one or two boundary edges in Edit Mode and instantly generate an adjoining quad face via the right-click context menu.

The tool includes options for controlling face rotation, balancing face direction along curves, and handling intersection corners symmetrically. Additional settings permit extruding new faces without merging the resulting geometry when specific topological control is required.