Connect your AI assistant

Herobrain is a remote MCP server. You add it to your assistant once, sign in with Google or GitHub, and its build tools show up in your chats. It takes about two minutes.

Server URL

https://herobrain.net/mcp

Streamable HTTP. For older clients that only speak SSE, use https://herobrain.net/sse. Sign-in is OAuth: you never paste a password or a key into your assistant.

Beta allowlist. Signing in only works for accounts that have been added to the beta. Request beta access first if you have not been added yet, and sign in later with the same email.

Claude (web and desktop app)

  1. Open Customize → Connectors.
  2. Click + → Add custom connector.
  3. Name it Herobrain, paste the server URL and click Continue.
  4. Leave the OAuth settings as they are and click Add.
  5. Sign in with Google or GitHub on the Herobrain page that opens, using your beta account.
  6. In a chat, click + → Connectors and switch Herobrain on.

It worked if Herobrain shows as Connected and its page lists the tools. The desktop app uses the same connectors as claude.ai. The free plan allows one custom connector. On Team and Enterprise plans an owner adds it once under Organization settings → Connectors.

Claude Code

Run this in your terminal:

claude mcp add --transport http herobrain https://herobrain.net/mcp

Then start Claude Code, type /mcp, pick herobrain and sign in in the browser. Add --scope user before the name to use it in every project.

ChatGPT

Custom MCP servers depend on your ChatGPT plan and workspace settings, and we have not tested every plan yet. If you don't see the option, use one of the other assistants.

  1. Open Plugins and click + → Add custom MCP server.
  2. Enter the name Herobrain, a short description and the server URL.
  3. Set authentication to OAuth, accept the warning and create it.
  4. Sign in with Google or GitHub when asked.
  5. In a chat, type @ and pick Herobrain. ChatGPT asks you to confirm each build.

Cursor

Add this to ~/.cursor/mcp.json (all projects) or .cursor/mcp.json (one project): 

{
  "mcpServers": {
    "herobrain": {
      "url": "https://herobrain.net/mcp"
    }
  }
}

Cursor opens the Herobrain sign-in page the first time it connects.

VS Code (GitHub Copilot)

Run MCP: Add Server from the Command Palette and choose HTTP, or add this to .vscode/mcp.json (or your user configuration via MCP: Open User Configuration): 

{
  "servers": {
    "herobrain": {
      "type": "http",
      "url": "https://herobrain.net/mcp"
    }
  }
}

VS Code opens a browser window to sign in on the first connection. Use Copilot Chat in agent mode.

Windsurf

In Cascade, open the … menu → Open MCP config file and add: 

{
  "mcpServers": {
    "herobrain": {
      "serverUrl": "https://herobrain.net/mcp"
    }
  }
}

Save, then sign in when Windsurf asks.

Other MCP clients

Any client that supports remote MCP servers with OAuth works the same way: add a server, paste the URL and sign in when it asks.

Clients that only run local (stdio) servers can use the mcp-remote bridge, which needs Node.js: 

{
  "mcpServers": {
    "herobrain": {
      "command": "npx",
      "args": [
        "mcp-remote",
        "https://herobrain.net/mcp"
      ]
    }
  }
}

Scripts and agent frameworks without OAuth can use an API key instead: create one in your account and send it as Authorization: Bearer hb_… to the server URL.

Your first build

Once connected, paste this into a new chat:

Use Herobrain to build a small stone watchtower next to a river. Before you start, ask me about the block palette and the roof shape. Then show me the renders and tell me what you would improve.

More ideas to try:

  • "Build a cozy two-storey cottage with a hip roof, and show me a section through the ground floor."
  • "Make a fantasy lighthouse on a small rocky island, then render it from the back."
  • "Read the script of my last build and make the walls deeper with stone trim."

You make the design calls: palette, gradient, floor plan. The assistant writes the WorldEdit script, gets renders back and corrects it. Saved builds get a page in the gallery with a 3D viewer and a .schem download.

Troubleshooting

Sign-in says I don't have access
The beta is invite-only. Sign in with the same Google or GitHub email you used to request access. If you have both, try the other provider.
The connector shows "Connect" or "Reconnect", or sign-in never finishes
Sign-in didn't complete. Allow the pop-up or new tab and sign in again. Removing the connector and adding it again also resets it.
A tool is missing, or the assistant uses an old version
Clients cache the tool list. After we update Herobrain, refresh it and start a new chat:
  • Claude: remove the connector and add it again.
  • Claude Code: /mcp → herobrain → Reconnect.
  • ChatGPT: open the plugin's settings and click Refresh.
  • Cursor and Windsurf: switch the server off and on again.
  • VS Code: run MCP: Reset Cached Tools.
The assistant doesn't use Herobrain
Check the connector is switched on for this chat and mention it by name, as in the prompt above.