When a tab’s folder holds an Unreal Engine project (a .uproject file), the project’s icon on its group’s row is Unreal Engine’s logo, with its name and engine in its tooltip, such as NightOwl · UE 5.4, and its menu has the actions below. Unreal Engine 4 projects work too.

The engine

Claudette looks for the engine the project uses, in this order:

1. The folder you picked with Choose engine folder… (Choose another engine folder… once one is found). It must hold Engine/Build/Build.version, though you can pick the Engine folder itself. Claudette remembers the pick for the project.
2. For a project with no engine named, or an empty name, an engine in a folder above the project.
3. For a project that names a version such as 5.4, the Epic Games Launcher’s install of it. On Linux there’s no launcher.
4. For anything else, usually a long ID, a build registered with Unreal’s version selector.

The menu’s header says which engine it found, its version, folder and kind: launcher install, source build, installed build, engine in a parent folder, or chosen by you. When none is found, it says so, the engine’s actions are greyed out (“The engine wasn’t found: choose its folder in this menu.”) and Choose engine folder… is offered.

Actions

Action	What it does
Launch editor	Opens the project in the editor. It’s the main action, and it’s greyed out until the editor is built.
Generate project files	A job that makes the project files for the IDE you chose. Greyed out for a project with no C++ code.
Build editor	A job that builds the project’s editor target.
Build and launch	Builds the editor, then launches it if the build succeeded.
Open solution	Opens the project’s solution. Greyed out with “Generate project files first.” until it exists. With Rider chosen, it’s Open in Rider instead (below).
Open latest log	Opens the project’s latest log in another app, once the editor has made one. While the editor runs, its log is also a row under the tab: see Editor logs.
Clean intermediates…	Deletes generated folders. It asks first.
End all Unreal editors…	Ends every running Unreal editor. It asks first.

The project’s menu also has Editor configuration, with Development and DebugGame as radio items. DebugGame loads the project’s DebugGame modules, and the labels say so: Launch editor (DebugGame), Build editor (DebugGame). A project’s own choice is remembered on this machine, and the default for projects that haven’t one is Settings → Project tools → Unreal Engine → Default editor configuration.

Open solution and Open in Rider

Open solution opens the Visual Studio solution, the Xcode workspace or the VS Code workspace, whichever the Project files for setting says Generate project files makes. It opens it with the OS’s app, or the IDE you chose in Open solutions with.

With Open solutions with set to Rider, the action reads Open in Rider and opens the .uproject itself, on every OS. Rider has its own Unreal project model, so there are no project files to generate first, and none to regenerate when you add source files. Rider reads a .uproject from Unreal Engine 4.25.4 on Windows and 4.26 on macOS and Linux. With an older engine, the action stays Open solution.

If Rider can’t be found, a note says so instead of letting the OS open the project in the Unreal editor. Choose Another program… in Settings → Project tools → All tools → Open solutions with to point at it.

The ones that ask first

• Clean intermediates… deletes Binaries and Intermediate in the project and in each plugin under Plugins/, and nothing else: not Saved, Content or Config. The question lists the folders and their total size, and warns when an editor seems to have the project open. Delete runs it as a job with its own run and log.
• End all Unreal editors… ends every Unreal editor running on this machine, not just this project’s, along with the processes each started, such as shader compilers. The question lists each with its PID and, when it can tell, its project. End it or End them ends them at once, and unsaved work in them is lost. The action is greyed out with “No Unreal editor is running.” when none is.

Settings

In Settings → Project tools, on this machine only: the Unreal Engine page, and All tools for Open solutions with.

Setting	Default	What it does
Recognize Unreal Engine projects	On	Off, Claudette treats an Unreal project’s folder as a plain folder: no engine actions, editor logs or note to Claude, though its own actions and links still work.
Tell Claude about Unreal Engine projects	On	Adds a note to the session with the engine’s version and folder and the commands to build the editor and regenerate project files, and asks Claude not to start the editor or packaging unless you ask. Applies to tabs started after the change.
Default editor configuration	Development	The configuration for projects that haven’t a choice of their own.
Project files for	Visual Studio on Windows, Xcode on macOS, VS Code on Linux	Which project files Generate project files makes, and which solution Open solution opens.
Open solutions with	The app the OS uses for it	The app the OS uses for it, Rider, Visual Studio, VS Code or Another program…, with Browse…. Unity and Godot solutions open the same way.

See also

• Unity and Godot, for the other engines.
• Actions and links, for commands of your own, such as a packaging script.
• Perforce, which many Unreal projects use.