# Spline MCP: connect your AI agent to Spline

Let Claude, ChatGPT, Cursor and other agents build 3D scenes (Spline) and 2D designs (Hana) with you. Every change lands in a live Spline file you can take over.

- Server URL: `https://mcp.spline.design/mcp` (streamable HTTP, OAuth; no API key)
- Page: https://spline.design/mcp
- Docs: https://docs.spline.design/generate/spline-mcp-server
- Desktop app (local server): https://spline.design/download

## How it works

1. You describe what you want in your agent.
2. The agent picks the Spline tools to call.
3. Spline MCP routes each call to your Spline editor: a browser tab (or, in ChatGPT, a panel in the chat), or the desktop app.
4. The editor makes the change on the live file, where you can watch, take over or keep editing.

Mention Spline (3D) or Hana (2D) in your prompt so the agent picks the right one.

## Setup

Up to four ways in, depending on the client: **Plugin**, **MCP Server**, **Terminal**, **Spline Desktop**.

- Plugin: The Spline plugin, from the client’s own plugin directory.
- MCP Server: The hosted Spline MCP server, added by URL in the client's own settings: `https://mcp.spline.design/mcp` (streamable HTTP, OAuth sign-in with your Spline account). Calls run in Spline in your browser.
- Terminal: The same hosted server, added with the command-line agent (Claude Code, Codex, Grok Build).
- Spline Desktop: The Spline desktop app runs the server locally and registers it with the client on launch.

### Claude

#### MCP Server

1. **Copy the Spline URL.** You’ll paste it in the next step.
   Server URL: `https://mcp.spline.design/mcp`
2. **Open Settings › Connectors.** In Claude, go to Settings › Connectors and choose Add custom connector.
   [Open Claude settings](https://claude.ai/customize/connectors)
3. **Connect and sign in.** Name it Spline, paste the URL and sign in with your Spline account. Then ask for a scene or a design.

#### Terminal (Claude Code)

1. **Add it to Claude Code.** Run this in your terminal.

   ```sh
   claude mcp add --transport http spline https://mcp.spline.design/mcp
   ```
2. **Authenticate.** In Claude Code, run `/mcp`, pick `spline` and choose Authenticate.
3. **Sign in and ask.** Sign in with your Spline account and allow access. Then ask for a scene or a design.

#### Spline Desktop

1. **Download Spline.** Install the desktop app and launch it. The local server runs there.
   [Download Spline](https://spline.design/download)
2. **It sets up Claude and Claude Code.** It adds its `Spline` server to `claude_desktop_config.json` for Claude and `~/.claude.json` for Claude Code. No manual config.
3. **Restart and ask.** Quit and reopen Claude, or start a new Claude Code session, then ask for a scene or a design.

### ChatGPT & Codex

#### Plugin (recommended)

1. **Add the Spline plugin.** Open its listing and add it. The same plugin works in ChatGPT and Codex.
   [Add to ChatGPT](https://chatgpt.com/plugins/plugin_asdk_app_6acd235a70a48191812b3ba9c471b4ac)
2. **Sign in.** Sign in with your Spline account when it asks. No API key.
3. **Ask away.** Ask for a scene or a design. Mention Spline (3D) or Hana (2D) so it picks the right one.

#### MCP Server

1. **Copy the Spline URL.** You’ll paste it in the next step.
   Server URL: `https://mcp.spline.design/mcp`
2. **Open Apps & Connectors.** In ChatGPT, go to Settings › Apps & Connectors and add a connector.
   [Open ChatGPT settings](https://chatgpt.com/#settings/Connectors)
3. **Connect and sign in.** Paste the URL and sign in with Spline. When you ask, the editor opens in a panel in the chat.

#### Terminal (Codex)

1. **Add it to Codex.** Run these in your terminal. Codex’s desktop app, CLI and IDE extension share this setup, so it works in all three.

   ```sh
   codex mcp add spline --url https://mcp.spline.design/mcp
   codex mcp login spline
   ```
2. **Sign in.** The login command opens your browser: sign in with Spline and allow access.
3. **Ask away.** Mention Spline (3D) or Hana (2D) in your prompt so it picks the right one.

#### Spline Desktop

1. **Download Spline.** Install the desktop app and launch it. The local server runs there.
   [Download Spline](https://spline.design/download)
2. **It sets up ChatGPT and Codex.** It registers its `Spline` server in `~/.codex/config.toml`, which the ChatGPT app, the Codex CLI and its IDE extension all read.
3. **Restart and ask.** Restart the ChatGPT app, or start a new Codex session. It connects the first time you ask for Spline.

### Grok

#### MCP Server

1. **Copy the Spline URL.** You’ll paste it in the next step.
   Server URL: `https://mcp.spline.design/mcp`
2. **Add a custom connector.** On grok.com, open Connectors, choose New Connector and then Custom.
   [Open Grok connectors](https://grok.com/connectors)
3. **Connect and sign in.** Paste the URL and sign in with your Spline account. Custom connectors need a paid Grok plan.

#### Terminal (Grok Build)

1. **Add it to Grok Build.** Run this in your terminal.

   ```sh
   grok mcp add --transport http spline https://mcp.spline.design/mcp
   ```
2. **Check and sign in.** Run `grok mcp doctor spline` to check it connects, and sign in with your Spline account when it asks.
3. **Ask away.** Mention Spline (3D) or Hana (2D) in your prompt so it picks the right one.

### Cursor

#### MCP Server

1. **Add it to Cursor.** One click, or add `spline` with the URL to `~/.cursor/mcp.json`.
   [Add to Cursor](cursor://anysphere.cursor-deeplink/mcp/install?name=spline&config=eyJ1cmwiOiJodHRwczovL21jcC5zcGxpbmUuZGVzaWduL21jcCJ9)
2. **Connect.** Open Settings › MCP and connect Spline.
3. **Sign in and ask.** Sign in with your Spline account and allow access. Then ask for a scene or a design.

#### Spline Desktop

1. **Download Spline.** Install the desktop app and launch it. The local server runs there.
   [Download Spline](https://spline.design/download)
2. **It sets up Cursor.** It adds its `Spline` server to `~/.cursor/mcp.json`. No manual config.
3. **Restart and ask.** Restart Cursor, or refresh the server list in Settings › MCP.

### VS Code

#### MCP Server

1. **Add it to VS Code.** One click, or add `spline` with the URL to your `mcp.json`.
   [Add to VS Code](vscode:mcp/install?%7B%22name%22%3A%22spline%22%2C%22type%22%3A%22http%22%2C%22url%22%3A%22https%3A%2F%2Fmcp.spline.design%2Fmcp%22%7D)
2. **Start and sign in.** Start the server and sign in with your Spline account when VS Code asks.
3. **Ask in agent mode.** In Copilot’s agent mode, mention Spline (3D) or Hana (2D).

#### Spline Desktop

1. **Download Spline.** Install the desktop app and launch it. The local server runs there.
   [Download Spline](https://spline.design/download)
2. **It sets up VS Code.** It adds its `Spline` server to your profile’s `mcp.json`. No restart needed.
3. **Restart and ask.** Accept the trust prompt, then ask in agent mode: Copilot starts it on first use.

### Antigravity

#### MCP Server

1. **Add it to Antigravity.** Add this to `~/.gemini/config/mcp_config.json`, inside `mcpServers` if you already have servers there.

   ```json
   {
     "mcpServers": {
       "spline": {
         "serverUrl": "https://mcp.spline.design/mcp"
       }
     }
   }
   ```
2. **Sign in.** Reload its MCP servers (Customizations › Installed MCP Servers) and sign in with your Spline account when it asks.
3. **Ask away.** Mention Spline (3D) or Hana (2D) in your prompt so it picks the right one.

#### Spline Desktop

1. **Download Spline.** Install the desktop app and launch it. The local server runs there.
   [Download Spline](https://spline.design/download)
2. **It sets up Antigravity.** It adds its `Spline` server to `~/.gemini/config/mcp_config.json`. No manual config.
3. **Restart and ask.** Restart Antigravity, or refresh its MCP list, then ask for a scene or a design.

### Other MCP clients

#### MCP Server

1. **Copy the Spline URL.** You’ll paste it in the next step.
   Server URL: `https://mcp.spline.design/mcp`
2. **Add it to your client.** Add a remote MCP server (streamable HTTP) with the URL.
3. **Connect and sign in.** Sign in with your Spline account when it asks, then ask for a scene or a design.

#### Spline Desktop

1. **Download Spline.** Install the desktop app and launch it. The local server runs there.
   [Download Spline](https://spline.design/download)
2. **It sets up the rest.** In the app, Settings › MCP › Other agents gives you the entry to paste, paths resolved.
3. **Restart and ask.** Paste it into your client’s MCP config (Windsurf, say) and restart it.

## Briefs to start from

### 3D scenes

- **Product hero**: A lit product scene, ready to embed.
  > In Spline, build a hero scene for a pair of wireless earbuds: the open case on a soft pedestal, studio lighting and a slow turntable, framed for a landing page.
- **Floating island**: A small world with light and water.
  > In Spline, build a floating island with a waterfall, a few trees and soft morning light, then frame the camera on it.
- **Generated character**: A generated model, placed and lit.
  > In Spline, generate a low-poly fox, sit it on a mossy rock and light the scene for golden hour.

### Interactive

- **Hover and click**: States and events on what you select.
  > In Spline, make the selected object lift and glow on hover, and bounce when it’s clicked.
- **Tiny game level**: A playable level with physics.
  > In Spline, build a small platformer level: floating platforms, a cube I roll with the arrow keys, and three coins that disappear when I touch them.

### Hana screens

- **Pricing page**: Desktop and mobile frames, editable.
  > In Hana, design a pricing page for a coffee subscription with three plans, as desktop and mobile frames.
- **Dark theme and back to code**: A restyled screen, exported as HTML.
  > In Hana, switch this screen to a dark theme, then export it back to HTML and CSS.
- **From your code**: Your component as a frame to edit. Needs an agent with your project open (Claude Code, Cursor).
  > Rebuild the hero from src/Hero.tsx as a Hana frame I can edit.

## Privacy and security

- **Your account, your grant.** Agents sign in with OAuth as you. Each grant belongs to one person, and revoking it stops its tokens working.
- **Calls stay in their conversation.** Each chat’s calls run in the editor it opened, never in another conversation’s file.
- **Or keep it local.** With the desktop app the server binds to 127.0.0.1, behind an origin allowlist, and is never reachable from the network.

## Frequently asked questions

### Do I need an API key?

No. Your agent signs in with your Spline account through OAuth, the first time it connects. There’s no key to create, paste or keep safe.

### Is there a Spline plugin?

Yes, for ChatGPT and Codex. Pick your agent at the top of the page to add it, or connect the Spline MCP server by URL in any other MCP client.

### Do I need the Spline desktop app?

No. Add the remote server to your agent and sign in, and its calls run in Spline in your browser. The desktop app is the alternative if you want the server running locally, and it sets up supported agents for you.

### Where do the agent’s changes happen?

In a real Spline file. In ChatGPT the editor opens in a panel in the conversation; other agents give you a link that opens the file in your browser, so you can watch, take over or keep editing yourself.

### Which agents work with it?

Any MCP client that supports remote servers (streamable HTTP) with OAuth sign-in, including Claude Code, Claude Desktop, ChatGPT, Codex, Cursor, VS Code, Antigravity, Grok and Grok Build.

### The Spline tools don’t appear in my agent

Check the server URL is `https://mcp.spline.design/mcp` and that you finished signing in; most agents show a sign-in or authenticate action next to the server. Some only load MCP servers at startup, so restart the agent after adding it.

### How do I disconnect an agent?

Remove the Spline server from that agent’s MCP settings. Its grant is tied to your account, and revoking it stops the agent’s tokens working right away.