UI Editor is AGE's tool for designing and building graphical user interfaces (GUIs) from AGE components. It allows you to design and build widgets and windows using on-screen forms using the same widgets that will be used in your application. Components created with UI Editor can be previewed so that you can ensure that they will look and feel exactly as you intended.

An important feature is the ability to integrate the GUI into your render scene and the render scene into your GUI, (example: graphical windows). In UI Editor, widget positions and sizes are organized by layout managers. this is an easy and fast way in order to choose the correct position and size of the widgets. UI Editor fully supports the AGE Resource System, allowing resources to be specified alongside windows as they are designed. This is an method to help designers and developers manage the resources that are needed by applications.