Getting Started

This walkthrough gets you from a fresh install to editing a C++ function next to the Blueprint node that calls it.

1. Enable the plugin

Enable AI Node Code Editor in Edit → Plugins, then restart the editor if prompted. It is an editor-only plugin and needs no extra project setup.

Note

This plugin only works in a C++ project (or a Blueprint project with the C++ toolchain installed). It reads and writes real .h and .cpp files, so you need a compiler set up the way Unreal’s Live Coding expects.

2. Add an AI API key (optional, for the AI features)

The editor itself works without any key. To use the AI assistant and AI inline completions, add a key for at least one provider:

1. Get an API key from Anthropic (Claude) or OpenAI (ChatGPT).

2. Open Edit → Project Settings → Plugins → Code Editor.

3. Paste it into Claude API Key or OpenAI API Key. Pick your Default Chat Agent to match.

See Settings for the full list, including the model name and endpoint per provider.

Caution

Your API key is stored in your local per-project editor settings (EditorPerProjectUserSettings). Treat it like any other secret: don’t commit the file that holds it, and don’t share your config.

3. Open the Code Editor

The editor lives inside the Blueprint editor, not as a standalone window.

1. Open any Blueprint (or a C++ class’s Blueprint child) so a Blueprint editor is focused.

2. Click the Toggle Code Editor button on the Blueprint editor toolbar, or press Alt + C.

A docked Code Editor tab appears (by default near the bottom of the Blueprint editor layout). Press Alt + C again to hide it.

Tip

You can also summon it from the Blueprint editor’s Window menu, listed as Code Editor. Drag the tab anywhere in the layout to dock it where you like.

4. Select a C++ function node

Click a node in the graph that calls a C++ function (a UFUNCTION exposed to Blueprint). The editor loads that function’s code automatically:

• the Implementation pane (.cpp) shows the function body (the default view),
• the Declaration pane (.h) shows its signature.

By default each pane loads the function in isolation (just that function, not the whole file) so you can focus on the code behind the node.

Note

If a node is not backed by editable C++ (a pure Blueprint function, an engine node whose source is read-only, or a node with no resolvable source), the editor has nothing to load or shows the file as read-only. Pick a node from your own C++ classes to follow along.

5. Edit, then Save and Build

1. Make a change in the Implementation pane. A filled dot on the tab marks unsaved changes.

2. Press Ctrl + S to save to disk, or Ctrl + Shift + B to Save and Build, which writes your changes and kicks off a Live Coding compile.

3. Watch the build output. When Live Coding finishes, your patched function is hot-reloaded into the running editor.

Caution

Save and Build uses Unreal’s Live Coding, which has the same limits here as anywhere: it hot-reloads function bodies well, but changes to headers (new UPROPERTY/UFUNCTION, changed signatures, new members) often need a full editor restart and a normal compile. Keep edits to function bodies for the fastest loop.

Where to go next

• Learn the panel layout in The Code Editor.
• Turn on AI completions to write code faster.
• Skim the Keyboard Shortcuts so the common actions are at your fingertips.