Better-Auth MCP server for AI agents

Better Auth MCP Server provides an enterprise-grade authentication solution with secure credential management, multi-protocol authentication (OAuth2, SAML, LDAP), and real-time threat detection. It's designed to integrate seamlessly with your applications and enhance your authentication workflows.

Installation

Via Smithery

Install Better Auth MCP Server automatically using Smithery:

npx -y @smithery/cli install @nahmanmate/better-auth-mcp-server --client claude

Manual Configuration

To use with Claude Desktop, add the server configuration to your Claude config file:

MacOS:

~/Library/Application Support/Claude/claude_desktop_config.json

Windows:

%APPDATA%/Claude/claude_desktop_config.json

Add the following configuration:

{
  "mcpServers": {
    "better-auth-mcp-server": {
      "command": "node",
      "args": ["/path/to/better-auth-mcp-server/build/index.js"],
      "disabled": false,
      "alwaysAllow": []
    }
  }
}

Configuration

Required Environment Variables

Set up the following environment variables for authentication:

# Required
BETTER_AUTH_PROJECT_ID=your-project-id
BETTER_AUTH_API_KEY=your-api-key

# Optional
BETTER_AUTH_ENV=development|staging|production
LOG_LEVEL=info|debug|error

Security Best Practices

For optimal security:

Store API keys in environment variables
Rotate keys regularly
Use different keys per environment
Implement rate limiting
Configure IP allowlists
Enable audit logging
Monitor authentication failures

Usage

Core Tools

The server provides several useful tools for authentication management:

Project Setup and Analysis

// Initialize Better-Auth in your project
await mcp.useTool('setup_better_auth', {
  projectPath: './my-next-app',
  config: {
    projectId: process.env.BETTER_AUTH_PROJECT_ID,
    apiKey: process.env.BETTER_AUTH_API_KEY
  }
});

// Analyze project structure for auth recommendations
await mcp.useTool('analyze_project', {
  projectPath: './my-next-app'
});

Testing Authentication

// Test core authentication flows
await mcp.useTool('test_auth_flows', {
  flows: ['login', 'register', '2fa']
});

// Run security checks
await mcp.useTool('test_security', {
  level: 'comprehensive'
});

Migrating from Existing Auth Systems

If you're already using Auth.js or NextAuth, you can migrate to Better Auth:

// Analyze current auth implementation
await mcp.useTool('analyze_current_auth', {
  projectPath: './my-next-app'
});

// Generate migration steps
await mcp.useTool('generate_migration_plan', {
  projectPath: './my-next-app',
  currentAuthType: 'next-auth'
});

Monitoring and Analysis

// Review auth system logs
await mcp.useTool('analyze_logs', {
  timeframe: '24h'
});

// Set up real-time authentication monitoring
await mcp.useTool('monitor_auth_flows', {
  alertThreshold: 'medium'
});

Debugging

Since MCP servers communicate over stdio, you can use the MCP Inspector for debugging:

npm run inspector

This will provide a URL to access debugging tools in your browser.

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 "better-auth-mcp-server" '{"command":"node","args":["/path/to/better-auth-mcp-server/build/index.js"],"disabled":false,"alwaysAllow":[]}'

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": {
        "better-auth-mcp-server": {
            "command": "node",
            "args": [
                "/path/to/better-auth-mcp-server/build/index.js"
            ],
            "disabled": false,
            "alwaysAllow": []
        }
    }
}

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": {
        "better-auth-mcp-server": {
            "command": "node",
            "args": [
                "/path/to/better-auth-mcp-server/build/index.js"
            ],
            "disabled": false,
            "alwaysAllow": []
        }
    }
}

3. Restart Claude Desktop for the changes to take effect