UploadThing MCP server

The MCP UploadThing server enables AI assistants to upload files through the Model Context Protocol (MCP). This integration provides a straightforward way for AI systems to handle file uploads via UploadThing's service.

Installation

To get started with the MCP UploadThing server, make sure you have Node.js 22 or later installed on your system. Then follow these steps:

# Clone the repository
git clone https://github.com/yourusername/mcp-uploadthing.git

# Navigate to the project directory
cd mcp-uploadthing

# Install dependencies
npm install

Configuration

Before running the server, you need to set up your UploadThing credentials and configure the server.

Environment Variables

Create a .env file in the root directory of the project with the following variables:

UPLOADTHING_SECRET=your_uploadthing_secret_key
UPLOADTHING_APP_ID=your_uploadthing_app_id
PORT=3000  # Optional, defaults to 3000

Running the Server

After configuration, you can start the MCP server:

npm start

The server will start listening on the port specified in your environment variables (default: 3000).

Usage Examples

Basic File Upload

To upload a file through the MCP protocol, AI assistants can use the following endpoint:

POST http://localhost:3000/upload

Include the file in the body of the request with proper MCP formatting.

Configuration Options

You can customize the upload behavior by modifying the configuration:

// Example configuration object
const config = {
  allowedFileTypes: ['image/jpeg', 'image/png', 'application/pdf'],
  maxFileSize: 10 * 1024 * 1024, // 10MB
  uploadPath: '/custom/upload/path'
};

Integration with AI Systems

When integrating with AI assistants, ensure they're configured to use the MCP protocol with your server URL:

MCP_SERVER_URL=http://localhost:3000

Troubleshooting

Common Issues

• Authentication Errors: Verify that your UploadThing credentials are correct in the .env file
• File Size Limits: Check if the uploaded file exceeds the size limits set in your UploadThing account
• File Type Restrictions: Ensure the file type is allowed in your configuration

Server Logs

Monitor the server logs for detailed information about uploads and potential errors:

npm start -- --verbose

How to install this MCP server

For Claude Code

To add this MCP server to Claude Code, run this command in your terminal:

claude mcp add-json "uploadthing-mcp" '{"command":"npx","args":["-y","uploadthing-mcp"]}'

See the official Claude Code MCP documentation for more details.

For Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > Tools & Integrations and click "New MCP Server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "uploadthing-mcp": {
            "command": "npx",
            "args": [
                "-y",
                "uploadthing-mcp"
            ]
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explicitly ask the agent to use the tool by mentioning the tool name and describing what the function does.

For Claude Desktop

To add this MCP server to Claude Desktop:

1. Find your configuration file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

2. Add this to your configuration file:

{
    "mcpServers": {
        "uploadthing-mcp": {
            "command": "npx",
            "args": [
                "-y",
                "uploadthing-mcp"
            ]
        }
    }
}

3. Restart Claude Desktop for the changes to take effect