MCP server · Built in

An MCP server made for
Unreal Engine graphs.

Connect Claude, Cursor, or any MCP client to GraphDeck and your AI assistant gets a real node canvas to work on: it builds Unreal Engine Blueprints and Materials live while you watch, validates its own output, teaches you how graphs work, and deploys to your project only with your approval.

Set it up in a minute Download GraphDeck Free →
Free and Pro · Claude Code · Claude Desktop · Cursor · VS Code · any MCP client · Localhost only
Live demo

Pick a path, watch it build

EventGraph● MCP connected
Settings · MCP Server
Enable MCP server
localhost:30303 · waiting for a client…
Event Actor Begin Overlap
Other Actor
Cast To BP_PlayerCharacter
Object
Cast Failed
As BP_Player…
Timeline DoorSlide
Play
Update
Finished
Direction
SET Door Alpha
Door Alpha
Set Relative Location
Target
New Location
✓ Validated · deployable · 97 / 100
ChatGPT
You are generating an Unreal Engine Blueprint as structured JSON. Follow the node library and pin rules below… - the full prompt GraphDeck copied
Here's the Blueprint in GraphDeck's format:
jsonCopy
{
  "nodes": [
    { "id": 1, "type": "Event ActorBeginOverlap" },
    { "id": 2, "type": "Cast To BP_PlayerCharacter" },
    { "id": 3, "type": "Timeline", "name": "DoorSlide" },
    …12 more nodes…
  ],
  "connections": [ ["1","2"], ["2","3"], … ]
}
Message ChatGPT…↑
Ctrl+V
Ctrl+C
Ctrl+V
✦Gemini - GraphDeck Blueprints
🔒gemini.google.com/gem/graphdeck-blueprints
✦GraphDeck BlueprintsGem · by GraphDeck
A door that slides open when the player walks into the trigger
Built against the Blueprint node rules - a Timeline drives the slide. Paste this back into GraphDeck:
jsonCopy
{
  "nodes": [
    { "id": 1, "type": "Event ActorBeginOverlap" },
    { "id": 2, "type": "Cast To BP_PlayerCharacter" },
    { "id": 3, "type": "Timeline", "name": "DoorSlide" },
    …12 more nodes…
  ],
  "connections": [ ["1","2"], ["2","3"], … ]
}
Ask GraphDeck Blueprints…➤
Ctrl+V
Ctrl+C
Ctrl+V
M_PulseLava● MCP connected
Settings · MCP Server
Enable MCP server
localhost:30303 · waiting for a client…
Texture Sample Noise_Tileable
UVs
RGB
A
Lerp
A
B
Alpha
Output
Material Result
Base Color
Metallic
Specular
Roughness
Emissive Color
Normal
✓ Validated · deployable · looks 92
ChatGPT
You are generating an Unreal Engine Material as structured JSON. Follow the node library and pin rules below… - the full prompt GraphDeck copied
Here's the Material in GraphDeck's format:
jsonCopy
{
  "nodes": [
    { "id": 1, "type": "TextureCoordinate" },
    { "id": 2, "type": "Panner", "speedX": 0.05 },
    { "id": 3, "type": "TextureSample", "texture": "Noise_Tileable" },
    …7 more nodes…
  ],
  "result": { "BaseColor": "@6", "EmissiveColor": "@8" }
}
Message ChatGPT…↑
Ctrl+V
Ctrl+C
Ctrl+V
✦Gemini - GraphDeck Materials
🔒gemini.google.com/gem/graphdeck-materials
✦GraphDeck MaterialsGem · by GraphDeck
Scrolling lava with a dark crust and a strong molten glow
Built against the Material node rules - Panner scrolls, Lerp blends, Emissive glows. Paste it back into GraphDeck:
jsonCopy
{
  "nodes": [
    { "id": 1, "type": "TextureCoordinate" },
    { "id": 2, "type": "Panner", "speedX": 0.05 },
    { "id": 3, "type": "TextureSample", "texture": "Noise_Tileable" },
    …7 more nodes…
  ],
  "result": { "BaseColor": "@6", "EmissiveColor": "@8" }
}
Ask GraphDeck Materials…➤
Ctrl+V
Ctrl+C
Ctrl+V
WBP_HealthBar● MCP connected
Settings · MCP Server
Enable MCP server
localhost:30303 · waiting for a client…
Health
DamageHeal
Designer preview · WBP_HealthBar
On Clicked Btn_Heal
Set Percent Prg_Health · 1.0
Target
In Percent
✓ Validated · tree + graph
ChatGPT
You are generating an Unreal Engine Widget as structured JSON. Follow the node library and pin rules below… - the full prompt GraphDeck copied
Here's the Widget in GraphDeck's format:
jsonCopy
{
  "widgetTree": { "Canvas_Root": [ "VBox_Main",
    "Txt_Title", "Prg_Health", "HBox_Buttons" ] },
  "eventGraph": { "nodes": [
    { "id": 1, "event": "On Clicked", "widget": "Btn_Heal" },
    { "id": 2, "call": "Set Percent", "target": "Prg_Health" },
    …
  ] }
}
Message ChatGPT…↑
Ctrl+V
Ctrl+C
Ctrl+V
✦Gemini - GraphDeck Widgets
🔒gemini.google.com/gem/graphdeck-widgets
✦GraphDeck WidgetsGem · by GraphDeck
A health bar with heal and damage buttons
Built against the Widget rules - tree plus two click events. Paste it back into GraphDeck:
jsonCopy
{
  "widgetTree": { "Canvas_Root": [ "VBox_Main",
    "Txt_Title", "Prg_Health", "HBox_Buttons" ] },
  "eventGraph": { "nodes": [
    { "id": 1, "event": "On Clicked", "widget": "Btn_Heal" },
    { "id": 2, "call": "Set Percent", "target": "Prg_Health" },
    …
  ] }
}
Ask GraphDeck Widgets…➤
Ctrl+V
Ctrl+C
Ctrl+V

Let your AI assistant use GraphDeck Best way

MCP server, built in

Connect an assistant like Claude and it drives the whole workflow: it builds graphs live on your canvas, looks things up in your library, and checks its own work against GraphDeck's validation. With the Connector plugin it reaches into Unreal too - pull Blueprints and Materials in, deploy back, compile and verify. You approve anything that touches your library or your project, and Ctrl+Z undoes any build.

Claude Code · Claude Desktop · Cursor · VS Code · any MCP client · Free and Pro
Set it up in a minute →More about the Unreal Engine MCP server →

Copy-prompt workflow

No API key needed

GraphDeck builds a detailed prompt for you. Copy it, paste into whatever AI you already use (ChatGPT, Claude, Gemini), and paste the response back - GraphDeck turns it into a wired, validated graph.

Works with any AI · Requires a free account with the AI provider

GraphDeck Gems

No API key needed

Pre-built Gemini Gems: custom AIs that already know every node, pin type, and syntax rule for each mode. Copy a short prompt, paste it in, copy the response back. Same clipboard flow, better results.

Requires a free Google account · Powered by Gemini
Blueprints Gem →Materials Gem →

Direct API key

Optional

Plug in your own API key from Anthropic or OpenAI and generate directly inside GraphDeck. Faster if you're doing a lot of generation, and the cost per graph is fractions of a penny.

Your key · Your account · Stored locally · Pay per use

Four ways to bring your AI - the MCP path shows Claude driving the canvas over the built-in server.

What the assistant can do

A canvas, not a text dump

Most AI-to-Unreal setups make the assistant describe nodes in text, or poke at your project files directly. GraphDeck's MCP server gives it a proper staging ground instead.

Build graphs live

The assistant generates Blueprints, Materials, and Widgets straight onto the canvas while you watch. Every build is one Ctrl+Z away from gone.

Check its own work

It verifies node names against the real UE node library before using them, and runs every build through GraphDeck's validation pipeline: wrong pins and broken wiring get caught and fixed before you ever see them.

Teach on the canvas

Ask it to explain a graph and it draws the lesson: rings, arrows, and step-by-step walkthroughs anchored to the actual nodes, with the camera gliding between them.

Use your library

It can search your saved graphs and reference material, open files, and build on what you've already made instead of starting cold.

Deploy to Unreal

With the free Connector plugin, the assistant can send a finished graph into your project as a compiled asset - and then compile-check it in the editor to prove it works.

Stay approved

Anything that touches your library or your Unreal project asks first. The assistant proposes; you approve.

Why outside the editor

A staging ground, not a scalpel

AI mistakes land on a canvas, not in your .uassets

MCP servers that live inside the Unreal editor hand the assistant your actual project. That's powerful, and sometimes exactly what you want - but it means every AI mistake happens in the real thing. GraphDeck keeps generation, iteration, and teaching on a separate canvas. Your project only changes at one explicit moment: when you deploy.

It works with Unreal's own MCP, not against it

Unreal Engine 5.8 ships a built-in MCP server, and the GraphDeck Connector plugin registers its tools with it (with its own local endpoint on older engine versions). That gives an assistant the full round trip: build and validate in GraphDeck, deploy, then compile and verify inside Unreal.

Localhost only

The MCP server runs on your machine and talks to clients locally. No cloud relay, no account, no telemetry from the MCP surface.

Setup

Connected in about a minute

1
Enable the MCP server in GraphDeck

Turn it on under Settings → MCP Server. GraphDeck shows the exact local address your client needs, and you pick which capability groups the assistant gets.

2
Add it to your MCP client

Claude Code, Claude Desktop, Cursor, VS Code, or anything else that speaks MCP. The docs have copy-paste config for each.

3
Ask for a graph

"Build me a door that opens on overlap." The assistant builds it on the canvas, validates it, and waits for your verdict.

FAQ

Common questions

What is an MCP server for Unreal Engine?

MCP (Model Context Protocol) is the open standard AI assistants use to control other software through tools. GraphDeck ships a built-in MCP server, so an assistant like Claude can build, validate, explain, and deploy Unreal Engine Blueprints and Materials through GraphDeck's canvas.

Which clients work?

Any MCP client: Claude Code, Claude Desktop, Cursor, VS Code, and others. If it speaks MCP, it can drive GraphDeck.

Can the AI break my Unreal project?

The AI works on GraphDeck's canvas, outside your project. Deploys are explicit and approved by you, canvas builds undo with Ctrl+Z, and deployed assets are standard Unreal assets you can open, inspect, and compile like anything built by hand.

Is it free?

Yes. The MCP server ships in both GraphDeck Free and Pro, and the Connector plugin is free.

Do I need the Connector plugin?

No. Without it, the assistant builds and validates on the canvas and you paste the result into Unreal via native clipboard export. The Connector adds one-click deploy and the in-editor verification tools.

Get started

Give your assistant a canvas

Read the setup docs Download GraphDeck Free →