The builder
Arrange: the builder
Arrange is the window where you build your world by hand. It opens on top of your game, gives you a set of tools, and writes what you make back into your project.
Opening it
Every chat header carries four controls for the game it belongs to: Play, Arrange, Stop and Save. Arrange opens your world in a window you can work in. Play runs the game as a player would see it.
Both Play and Arrange are unavailable until a project is open. If they are greyed out, the tooltip says why — "Open a project first" means there is no project bound to this chat yet.
Stage Engine runs one game at a time. If a game started from another chat is still running, starting this one is refused until you stop that one.
The Tools menu
The builder does not spread its tools across a wide toolbar. There is a single Tools pill; pressing it opens the menu of everything you can pick up. Once a tool is in your hand, that pill becomes the tool’s own icon, and pressing it opens the same menu again so you can switch.
Two rows at the top of the menu are actions rather than tools. Assets opens the library of things you can place. View drops a still from where you are standing, which is how a camera shot gets made.
Below the divider are the tools themselves: Sculpt, Paint, Plants, Water, Sky, Weather and Characters. People appears as well, but only when your world actually has people in it.
There is no Camera row in the Tools menu. Camera controls appear when you select a still you have already dropped with View — it is a state you enter by selecting something, not a tool you pick up.
Tools with a bar, and tools with a panel
Sculpt, Paint and Plants put a row of verbs on the bar — Raise, Lower, Texture, Plant and so on — and a panel of settings you can open beside them. Those are the tools you use by dragging on the world.
Water, Sky, Weather, Characters and People have no bar verbs. They are panels of settings for something that already exists in the world. Changing a slider changes the world; there is nothing to drag.
Some panels are built from whatever the thing you selected actually exposes rather than from a list we wrote down. That is deliberate: the panel shows the real controls of the real thing, so it stays correct when the thing changes.
Undo, redo and saving
Undo and redo sit on the shelf, and they appear only when there is a step to take. An empty history means no undo button at all rather than a greyed one.
You do not have to remember to save. Pressing Play or Arrange commits the work you have arranged on the way in. The Save control in the chat header is the manual version of something that already happens, and it stays pressable whether or not a game is running.