Pro Onlyv1.1.4+

AI CLI Integration Guide

How to control Unity from terminal-based AI tools like Claude Code, Codex CLI, and Gemini CLI.

ChatGPT Users Click Here

We prepared a detailed guide for those who want to control Unity with ChatGPT (Codex CLI).

About This Page

This guide is for users who want to control Unity with AI tools other than Claude Desktop, Cursor, or VS Code (Copilot).

If you're using Claude Desktop, Cursor, or VS Code (Copilot), please see the Setup Guide (one-touch configuration available).

Requirements

Node.js 18 or later (If not installed, nodejs.org to download)
One of the CLI tools (see below)
Synaptic AI Pro v1.1.4 or later

Install CLI Tool

Install the CLI tool for your preferred AI service.

Claude Code

Anthropic

Anthropic's official CLI. Powerful code understanding and generation.

npm install -g @anthropic-ai/claude-code

Codex CLI

OpenAI

OpenAI's official CLI. Available with ChatGPT Plus or higher.

npm install -g @openai/codex

Select 'Sign in with ChatGPT' after launchChatGPT Plus or higher

Gemini CLI

Google

Google's official CLI. Free tier available (60 requests/min).

npm install -g @google/gemini-cli

VS Code / Cursor Extensions

Various

For VS Code or Cursor extensions (like Codex extension), this method is also required.

Extensions cannot use the editor's MCP settings, so they connect via HTTP API.

How to Use (5 Steps)

Open Setup Window

In Unity menu: Tools → Synaptic Pro → Setup Window

Switch to HTTP Tab

Click HTTP Server tab to switch

Copy Prompt

Click Copy Prompt Template button

Paste to CLI

Paste the prompt to Claude Code, Codex CLI, Gemini CLI, etc.

Key Point

Since it just hits HTTP endpoints, CLI can run from any directory. The server is started from Unity, so no cd commands needed in CLI.

Now just talk to the AI. Try saying "create a red cube" to test it out.

"Create a red cube""Create a Cube for the Player""Move the MainCamera back a bit"

💡Pro Tip: Automate with Skills

Using CLI's Skills feature, you don't need to paste the template every time.

How to set up:

Copy prompt from Unity Setup Window's HTTP tab
Tell CLI: "Create a skill with this content"
From now on, the template is applied automatically

Thanks: Synaptic AI user

Start HTTP Server

Click Start HTTP Server button and you're done!

You're all set!

Now just talk to the AI. Try saying "create a red cube" to test it out.

Conversation Example

You:Start the MCP server

AI:I'll start the Synaptic AI Pro MCP server. Moving to Assets/Synaptic AI Pro/MCPServer folder and running node index.js...

You:Create a capsule for the player

AI:I'll use unity_create_gameobject to create a capsule. I'll name it 'Player'...

You:Add Rigidbody and enable gravity

AI:I'll add a Rigidbody component using unity_add_component...

Troubleshooting

'node: command not found' appears

Node.js is not installed. Please install from nodejs.org.

'Connection refused' appears

Check if Unity Editor is running. Also verify Synaptic AI Pro is installed.

AI cannot start the server

Make sure you're working in the Unity project folder. Check that Assets/Synaptic AI Pro/MCPServer folder exists.

[Windows] curl command doesn't work

On Windows PowerShell, 'curl' may be an alias for Invoke-WebRequest. Try using 'curl.exe http://localhost:8086/health' instead.

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