Funplay MCP for Unity exposes an execute_code tool that lets AI assistants run C# directly inside the Unity Editor. That means you can describe a scene in plain language and have your coding agent assemble it in one shot, with no copy-paste cycle.
What Funplay Unity MCP Is
Funplay MCP for Unity is an MIT-licensed MCP server that plugs into the Unity Editor and exposes 79 built-in tools to any connected AI assistant. Those tools cover scene creation, script generation, runtime verification, input simulation, performance analysis, and editor automation. The server runs locally at http://127.0.0.1:8765/ and works with Claude Code, Cursor, VS Code Copilot, Windsurf, and Codex.
Two tool profiles are available: core (19 tools) and full (79 tools). The core profile keeps things lightweight. The full profile opens up every capability, including execute_code.
Why This Matters
Without MCP integration, building a scene from an AI prompt means a tedious loop: ask the model for C#, copy the output into Unity, wait for compilation, fix errors, and repeat. With execute_code in the loop, the agent writes, executes, and validates code inside Unity without you touching the editor. One prompt can produce a complete scene hierarchy with GameObjects, materials, and attached scripts.
Prerequisites
- Unity 2022.3 or later
- A supported AI coding environment (Claude Code, Cursor, VS Code Copilot, Windsurf, or Codex)
- Funplay Unity MCP installed and the server running
Installation
Open Unity, navigate to Window → Package Manager → Add from git URL, and paste:
https://github.com/FunplayAI/funplay-unity-mcp.git
After installation, open Funplay → MCP Server in the Unity menu bar. The server starts on http://127.0.0.1:8765/ by default. Confirm the server is running before connecting your AI client.
Walkthrough: One Prompt, One Scene
Below is a concrete example using Cursor as the AI client. The same approach works in Claude Code, VS Code Copilot, Windsurf, or Codex.
Step 1 — Configure Your AI Client
Point your MCP client configuration at the local server. A minimal configuration might look like this:
```json { "mcpServers": { "funplay-unity": { "url