Getting Started

This guide walks you through installing the plugin, setting up an AI agent, and running your first prompt.

Prerequisites

  • Unreal Engine 5.5 or 5.6 (source or Launcher build)
  • Node.js 18+ — Required for CLI agents (Claude Code, Gemini CLI, Codex, etc.). The plugin auto-detects Node.js from common install paths and version managers (nvm, volta, fnm, bun, mise).
  • At least one AI agent CLI installed, or an OpenRouter API key for the built-in agent.

Installation

From Fab

  1. Purchase or download Blueprint AI from the Unreal Marketplace (Fab).
  2. Enable the plugin in Edit > Plugins and restart the editor.

Manual Install

  1. Copy the BlueprintAI folder into your project's Plugins/ directory.
  2. Regenerate project files and restart the editor.

Opening the Chat Panel

Once the plugin is enabled, open the chat panel from the menu bar:

Window > AI > Blueprint AI

The panel opens as a dockable tab. You can have multiple chat tabs open simultaneously, each connected to a different agent or session.

Agent Setup

Blueprint AI supports two categories of agents:

Built-in OpenRouter Agent (no CLI required)

  1. Go to Project Settings > Plugins > Blueprint AI.
  2. Paste your OpenRouter API key in the OpenRouter API Key field. Get one at openrouter.ai.
  3. Optionally change the Default OpenRouter Model (defaults to anthropic/claude-sonnet-4). You can also switch models per session from the chat UI.

CLI Agents (Claude Code, Gemini CLI, Codex, etc.)

CLI agents run as external processes and communicate via JSON-RPC over stdio. The plugin provides a one-click installer for each agent:

  1. Open the chat panel and select the agent from the dropdown at the top.
  2. If the agent isn't installed, the panel shows an Install button that installs both the base CLI and the ACP adapter package via npm or bun.
  3. Some agents require their own authentication (e.g., running claude login in your terminal before first use).

Your First Prompt

  1. Select an agent from the dropdown.
  2. Type a message in the input field, for example:
    Read the Blueprint at /Game/ThirdPerson/BP_ThirdPersonCharacter and summarize its event graph.
  3. The agent will call the read_file tool, read the Blueprint's structure, and respond with a summary.

Attaching Context

You can provide additional context to the AI by attaching Blueprint nodes, assets, or images:

  • Right-click a node in the Blueprint graph editor and select Select as Context. The node's pins, connections, and properties are serialized and sent with your next prompt.
  • Right-click an asset in the Content Browser and select Select as AI Context. The Blueprint's structure overview (variables, components, functions, events) is serialized.
  • Paste an image from your clipboard (Ctrl/Cmd+V) into the chat input. The image is base64-encoded and sent to vision-capable models.
  • Drag and drop Blueprint assets directly onto the chat input area.

What's Next?

  • Explore the full list of 25+ editor tools in the Tools Reference.
  • Learn how to set up agent profiles to restrict tools per domain in the Settings page.
  • Connect external MCP clients to the embedded MCP server for programmatic access.