VibeLink - Unity Agentic Bridge

Enable AI agents to see, manipulate, and verify Unity projects autonomously.

VibeLink is a hybrid Unity Package + MCP Server that gives CLI-based AI agents (Claude Code, Cursor, etc.) direct access to Unity's Editor through the Model Context Protocol.

Status: ✅ Working! See CURRENT_STATUS.md for latest test results and known issues.

Quick Test: After Unity restart, run ./test-after-restart.sh to verify all features work.

🎯 Core Capabilities ("The Superpowers")

🔴 Power 1: The Eyes (Visual Verification)

• Capture Game View or Scene View screenshots
• See what the agent creates in real-time
• Visual feedback loop for iterative development

🔵 Power 2: The Hands (Direct Manipulation)

• Execute C# code directly in Unity Editor
• No need to create files for quick operations
• Instant iteration and testing

🟢 Power 3: The Brain (State Querying)

• Query GameObject state using CSS-like selectors
• Get actual runtime values, not just code
• Verify scene configuration programmatically

🟡 Power 4: The Time Machine (Test Running)

• Enter Play Mode for specified duration
• Capture all logs and errors automatically
• Automated regression testing

🚀 Quick Start

Prerequisites

• Unity 2021.3 or later (.NET Standard 2.1 support)
• Node.js 18+ (for MCP server)
• AI agent that supports MCP (Claude Code, Cursor, etc.)

Installation

1. Install Unity Package

Copy the unity-package folder into your Unity project's Packages directory:

cd YourUnityProject/Packages
git clone https://github.com/vibelink/unity-vibe-link.git com.vibelink.unity

Or add via Package Manager:

1. Open Unity
2. Window → Package Manager
3. • → Add package from disk
4. Select unity-package/package.json

2. Install MCP Server

cd mcp-server
npm install
npm run build

3. Configure Your AI Agent

Add to your MCP config (e.g., ~/.config/opencode/mcp.json or Claude Desktop config):

{
  "mcpServers": {
    "vibelink-unity": {
      "command": "node",
      "args": ["/path/to/unity-vibe-link/mcp-server/build/index.js"]
    }
  }
}

4. Start Unity with VibeLink

1. Open your Unity project
2. Go to Tools → VibeLink → Start Host
3. The VibeLink window will show "Connected: Yes" when your agent connects

📖 Usage Examples

Example 1: Visual Verification

User: "The button looks off-center"

Agent:

1. unity_capture_view(viewType: "game")
2. [Analyzes screenshot]
3. unity_query_state(selector: "Button")
4. unity_execute_script(code: "GameObject.Find('Button').GetComponent<RectTransform>().anchoredPosition = Vector2.zero;")
5. unity_capture_view(viewType: "game")
6. [Verifies fix]

Example 2: Procedural Generation

User: "Create 50 cubes in a spiral pattern"

Agent:

unity_execute_script({
  code: `
    for (int i = 0; i < 50; i++) {
      float angle = i * 0.5f;
      float radius = i * 0.2f;
      Vector3 pos = new Vector3(
        Mathf.Cos(angle) * radius,
        i * 0.1f,
        Mathf.Sin(angle) * radius
      );
      GameObject cube = GameObject.CreatePrimitive(PrimitiveType.Cube);
      cube.transform.position = pos;
    }
  `
})

Example 3: Automated Testing

User: "Does the game crash when I start?"

Agent:

unity_run_playmode({ duration: 5.0 })
// Returns all logs/errors from 5-second playtest

🛠️ Available Tools

Tool	Description	Use Case
unity_capture_view	Screenshot Game/Scene view	Visual verification
unity_execute_script	Run C# code in Editor	Quick iterations
unity_query_state	Query GameObject state	State inspection
unity_run_playmode	Run game with logging	Automated testing
unity_ping	Check connection	Health check

🔒 Safety Features

Sandboxing

• All agent-created assets go to Assets/_AgentScratchpad/
• Prevents corruption of core project files

Watchdog (Coming Soon)

• Script execution timeout
• Infinite loop protection
• Resource usage monitoring

🏗️ Architecture

┌─────────────────┐         Named Pipe          ┌──────────────────┐
│  Unity Editor   │◄───────────────────────────►│   MCP Server     │
│  (C# Package)   │      <5ms latency           │   (Node.js)      │
└─────────────────┘                              └──────────────────┘
        ▲                                                 ▲
        │                                                 │
        │ EditorWindow                           MCP Protocol
        │ Direct API Access                      (JSON-RPC)
        │                                                 │
        ▼                                                 ▼
┌─────────────────┐                              ┌──────────────────┐
│  Unity Scene    │                              │   AI Agent       │
│  GameObjects    │                              │ (Claude/Cursor)  │
└─────────────────┘                              └──────────────────┘

📝 Development Status

• Core transport layer (Named Pipes)
• Visual capture (Game/Scene views)
• Script execution framework
• State querying with selectors
• Play Mode automation
• MCP server implementation
• Dynamic C# compilation (Roslyn)
• Advanced selector syntax
• Watchdog protection
• Performance profiling tools
• Asset modification tracking

🤝 Contributing

This is an open-source project! Contributions welcome.

Development Setup

1. Clone repository
2. Open Unity package in Unity 2021.3+
3. Run npm install in mcp-server/
4. Make changes and test with your AI agent

📄 License

MIT License - See LICENSE file for details

🔗 Links

• Model Context Protocol Spec
• Unity Named Pipes Reference
• Documentation

⚠️ Disclaimer

VibeLink is in alpha. Use in production projects at your own risk. Always backup your project before enabling agent automation.

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Built for the future of AI-assisted game development 🎮🤖