DhanHQ MCP Server

An MCP (Model Context Protocol) server for DhanHQ APIs with OAuth-based authentication for Individual Traders.

Overview

This server implements the complete three-step DhanHQ authentication flow that generates a JWT access token for API requests. The authentication process involves:

1. Step 1: Generate Consent - Creates a temporary session ID
2. Step 2: Browser-Based Login - User authenticates with 2FA
3. Step 3: Consume Consent - Exchanges tokenId for access token

Prerequisites

Before you begin, you need to generate your API Key and Secret:

1. Log in to web.dhan.co
2. Navigate to My Profile → 'Access DhanHQ APIs'
3. Toggle to 'API key'
4. Enter your:
   • App name
   • Redirect URL (e.g., http://localhost:3000/callback)
   • Optional Postback URL

Note: Generated API Keys and Secrets are valid for 12 months.

Setup

1. Install Dependencies

npm install

2. Configure Environment Variables

Copy .env.example to .env and fill in your credentials:

cp .env.example .env

DHAN_CLIENT_ID=your_dhan_client_id
DHAN_API_KEY=your_api_key
DHAN_API_SECRET=your_api_secret
REDIRECT_URL=http://localhost:3000/callback

3. Build the Project

npm run build

Usage

Development Mode

npm run dev

Using MCP Inspector (Recommended for Debugging)

The MCP Inspector provides an interactive interface to test the MCP tools:

npm run inspector

This will:

1. Start the MCP server
2. Open the MCP Inspector in your browser
3. Allow you to call tools and see responses in real-time

Authentication Flow

Step 1: Start Authentication

Call the start_authentication tool. This will:

• Validate your API credentials
• Create a temporary session (consentAppId)
• Return a login URL

Step 2: Browser Login

Open the provided login URL in your browser:

• Log in with your Dhan credentials
• Complete 2FA verification (OTP/PIN/Password)
• You'll be redirected to your configured Redirect URL with a tokenId parameter

Example redirect URL:

http://localhost:3000/callback?tokenId=abc123def456...

Step 3: Complete Authentication

Call the complete_authentication tool with the tokenId from Step 2:

• Exchanges the tokenId for a JWT access token
• Stores token details (expiry, client info, etc.)
• Returns the access token for use in subsequent API calls

Check Status

Use check_auth_status to view:

• Current authentication state
• Token validity
• Client information
• Token expiry time

Available MCP Tools

start_authentication

Initiates the DhanHQ authentication flow (Step 1).

• Input: None
• Output: consentAppId, loginUrl, instructions

get_login_instructions

Gets the login instructions and URL for Step 2.

• Input: consentAppId (optional)
• Output: loginUrl, detailed instructions

complete_authentication

Completes authentication with the tokenId from Step 2 (Step 3).

• Input: tokenId (required)
• Output: authToken with accessToken and client details

check_auth_status

Checks the current authentication status.

• Input: None
• Output: Authentication state and token validity

reset_authentication

Clears the current authentication state.

• Input: None
• Output: Success message

API Architecture

• Framework: Node.js with TypeScript
• Protocol: Model Context Protocol (MCP)
• Transport: Stdio
• Auth API: DhanHQ OAuth endpoints
• HTTP Client: Axios

Project Structure

src/
├── index.ts           # MCP server and tool handlers
├── authentication.ts  # Authentication logic (3-step flow)
├── config.ts         # Configuration management
└── types.ts          # TypeScript interfaces

Security Considerations

• API credentials are stored in environment variables
• Access tokens are stored in-memory (session-based)
• For production, use:
  • Secure credential storage
  • Database for token persistence
  • Token refresh mechanisms
  • HTTPS for callbacks
• The MCP Inspector output redacts sensitive tokens

Error Handling

The server includes comprehensive error handling:

• API request validation
• Network error handling
• Configuration validation
• Token expiry checking

Next Steps

After authentication is working:

1. Add API tools for trading operations
2. Implement token refresh logic
3. Add portfolio/holdings endpoints
4. Implement order placement tools
5. Add market data tools

Development Notes

• Logs are printed to stderr for debugging
• Authentication state is stored in-memory (lost on restart)
• For production, migrate to persistent storage
• MCP Inspector is recommended for interactive testing and debugging

License

MIT