Quick Start Guide

1 Prerequisites

Before installing CLAUDIUS, make sure you have the following:

• ✓
  Unreal Engine 5.4 or later

  CLAUDIUS supports UE 5.4, 5.5, 5.6, and 5.7. Earlier versions are not supported.

• ✓
  A UE5 Project

  You'll need an existing project or create a new one. Any template works.

• ✓
  Epic Games Launcher

  CLAUDIUS is installed via the Epic Marketplace, so you'll need the launcher.

2 Installing CLAUDIUS

Step 2.1: Download from Epic Marketplace

After purchasing CLAUDIUS from the Epic Marketplace, open the Epic Games Launcher and navigate to your Library.

Navigate to Library > Vault in the Epic Games Launcher

Step 2.2: Add to Your Project

Find CLAUDIUS in your Vault and click "Add to Project". Select your target project from the dropdown.

Select your project and click "Add to Project"

Step 2.3: Enable the Plugin

Open your project in Unreal Engine. Go to Edit > Plugins, search for "CLAUDIUS", and ensure it's enabled. Restart the editor if prompted.

// CLAUDIUS is added to your .uproject file
{
  "Plugins": [
    {
      "Name": "Claudius",
      "Enabled": true
    }
  ]
}

Step 2.4: CLAUDE.md Auto-Copy (v2.0.1+)

Good news! Starting in v2.0.1, CLAUDIUS automatically copies CLAUDE.md to your project root on first run. This file contains all command documentation that Claude Code uses to understand how to control your project.

Troubleshooting: Manual Copy (if needed)

If the automatic copy doesn't work, you can manually copy the file:

# Copy from plugin folder to project root:

# Source:
YourProject/Plugins/Claudius/CLAUDE.md

# Destination:
YourProject/CLAUDE.md

3 Sending Your First Command

CLAUDIUS supports two communication methods: file-based and HTTP. For this quick start, we'll use the file-based approach which is the simplest.

Step 3.1: Locate the Command File

The claudius_request.json file is located in Plugins/Claudius/. CLAUDIUS creates a template command file automatically on first run.

# Your project structure will look like this:
MyProject/
├── Content/
├── Config/
├── Plugins/
│   └── Claudius/
│       ├── claudius_request.json   # Write commands here
│       ├── claudius_response.json  # Responses appear here
│       └── CLAUDE.md               # Original AI docs
└── CLAUDE.md                       # Auto-copied for Claude Code

Step 3.2: Write a Simple Command

Open Plugins/Claudius/claudius_request.json and replace the template with the following command to list all actors in the current level:

{
  "command_id": "my_first_command",
  "category": "level",
  "command": "list_actors",
  "params": {}
}

Step 3.3: Save and Wait

Save the file. CLAUDIUS watches this file and will process the command within 500ms. The response will appear in claudius_response.json.

4 Verifying It Works

After saving your command, open claudius_response.json to see the result:

{
  "command_id": "my_first_command",
  "success": true,
  "message": "Listed 24 actors in current level",
  "timestamp": "2024-01-15T10:30:45.123Z",
  "execution_time_ms": 8.5,
  "output": {
    "actors": [
      { "name": "Floor", "class": "StaticMeshActor" },
      { "name": "DirectionalLight", "class": "DirectionalLight" },
      { "name": "SkyLight", "class": "SkyLight" },
      // ... more actors
    ],
    "count": 24
  }
}

Try Another Command: Spawn an Actor

Let's spawn a cube to confirm CLAUDIUS can modify your level:

{
  "command_id": "spawn_cube",
  "category": "level",
  "command": "spawn_actor",
  "params": {
    "class_path": "/Engine/BasicShapes/Cube.Cube",
    "location": { "x": 0, "y": 0, "z": 100 },
    "actor_label": "MyCube"
  }
}

Check your Unreal viewport - you should see a new cube appear at the origin!

A cube spawned at position (0, 0, 100) via CLAUDIUS command

5 Next Steps

You've successfully installed CLAUDIUS and sent your first commands. Here's what to explore next:

• Browse all commands: Check the CLAUDE.md file in your project for complete documentation of all 130+ commands across 19 categories.
• Try the HTTP API: For lower latency (~10-50ms), use the HTTP endpoint at http://127.0.0.1:8080/api/v1/commands.
• Integrate with Claude Code: Open your project folder in Claude Code - it will automatically read the CLAUDE.md file and understand how to control your project.
• Explore use cases: Check out the other tutorials for specific workflows like video production, CI/CD integration, and AI NPC control.