Editing the model

Press Edit model in the toolbar (you need editor access to the canvas). You are now working on a draft: nothing reaches your collaborators until you press Save. Drafts survive refreshes. An unsaved draft is restored when you come back, as long as nobody saved a newer version meanwhile.

• Add a node with Add node. If a node is selected, the new one is created inside it, one C4 level down (a system gets a container, anything else a component). Nothing selected creates at the top level.
• Connect nodes by dragging from the gold handles on a node's edge to another node.
• Configure everything about a node in the right panel — every field is covered in Node configuration.
• Delete nodes, edges, zones and flows from their panels, or press Backspace on the selection. Deleting from a panel asks first.
• Undo / redo with ⌘Z / ⇧⌘Z. Bursts of typing (or a whole assistant build) undo as one step.
• Save commits the draft as a new version with a history snapshot. Discard throws the draft away. (Labels in the timeline come from the assistant and from MCP, which name their own saves.)
• Conflicts: saves are version-locked. If someone saved while you edited, your save is refused instead of silently overwriting — reload, then re-apply.