Get Started with Horizon3.ai-Hosted MCP Server

Before you can authenticate and use the NodeZero MCP Server, you must configure it for use in your IDE or AI client.

Prerequisites

An IDE or AI client that supports streamable HTTP and OAuth 2.1
Node.js v18+ installed to run the local MCP proxy mcp-remote.
A modern browser for completing the OAuth login

Set Up Visual Studio Code w/ GitHub CoPilot

To set up the Horizon3-hosted MCP Server in Visual Studio Code, configure it for MCP Server:

Open the command palette in VS Code.
Click Show and Run Commands.
Run the command MCP: Add Server.
Select HTTP (HTTP or Server-Sent Events) as the type.
Enter the server URL:
- US: https://mcp.horizon3ai.com/mcp
- EU: https://mcp.horizon3ai.eu/mcp
Provide a name for the server (for example, horizon3-mcp-server).

Visual Studio Code creates an mcp.json file (or adds to it if it already exists) with the information you just entered:
```
{
    "servers": {
    "horizon3-mcp-server": {
        "url": "https://mcp.horizon3ai.com/mcp",
        "type": "http"
      }
    },
    "inputs": []
}
```
7. Once configuration is saved, VS Code will prompt you to authenticate to proxy.horizon3ai.com 8. After clicking Allow, login to your Horizon3 Portal Account following the redirect. Once you successfully login, close the browser and you're ready to get started!

Client Compatibility

The H3 MCP Server works with MCP-compliant clients that support both OAuth 2.1 authentication and HTTP streamable transport. This includes:

VS Code with MCP extensions - Fully compatible
Claude Code - Fully compatible
Claude Desktop - Currently has some known compatibility issues
Gemini CLI - Full compatible
Windsurf - Fully compatible

Set Up Other IDEs or Clients

To set up the Horizon3-hosted MCP Server for other IDEs or clients, create an mcp.json file in your workspace or home directory with an entry for the MCP Server:

In your client of choice, enter the server URL:
- US: https://mcp.horizon3ai.com/mcp
- EU: https://mcp.horizon3ai.eu/mcp
Use streamable HTTP as the transport mode
Begin the OAuth login process when prompted and complete using your NodeZero credentials after being redirected

{
   "servers": {
       "horizon3-mcp-server": {
           "url": "https://mcp.horizon3ai.com/mcp",
           "type": "http"
       }
   },
   "inputs": []
}