1

Open Settings

Navigate to Cursor → Settings → Cursor Settings → MCP
Cursor → Settings → Cursor Settings → MCP
2

Configure Server

Click “Add new Global MCP server” and add this configuration to mcp.json:
{
  "mcpServers": {
    "sei": {
      "command": "npx",
      "args": ["-y", "@sei-js/mcp-server"]
    }
  }
}
3

Restart

Restart Cursor to activate the MCP server. You’ll see a notification when it’s ready.

​
Wallet Connection

Wallet Tools Disabled by DefaultFor security, the MCP server runs in read-only mode by default. Only blockchain data tools are available without wallet configuration.

​
Default Behavior (Read-Only)

Without wallet configuration, you can:
  • ✅ Check balances and account data
  • ✅ Read smart contract data
  • ✅ Get network and block information
  • ✅ Search documentation
  • ❌ Send transactions or transfer tokens
  • ❌ Deploy or write to contracts
  • ❌ Approve token spending

​
Enabling Wallet Tools

To unlock transaction capabilities, add your private key to the configuration:
Use a dedicated test wallet with minimal funds. Never use your main wallet’s private key.
1

Get Private Key

Export your private key from your wallet:
  • Look for “Export Private Key” or “Show Private Key” in wallet settings
  • Ensure the key starts with 0x
  • Fund the wallet with small amounts for testing
2

Add to Configuration

Add the PRIVATE_KEY environment variable to your MCP configuration:
{
  "mcpServers": {
    "sei": {
      "command": "npx",
      "args": ["-y", "@sei-js/mcp-server"],
      "env": {
        "WALLET_MODE": "private-key",
        "PRIVATE_KEY": "YOUR_PRIVATE_KEY"
      }
    }
  }
}
3

Restart & Verify

Restart your AI assistant and verify wallet tools are available:Ask your AI: “What’s my wallet address?”If configured correctly, you’ll get your wallet address. If not, you’ll see an error message.

​
Environment Variables

​
WALLET_MODE

  • Type: string
  • Default: "disabled"
  • Description: Controls wallet functionality and transaction capabilities
  • Options: "disabled" | "private-key"

​
PRIVATE_KEY

  • Type: string
  • Default: -
  • Description: Private key for wallet operations (required when WALLET_MODE=“private-key”)
  • Format: 0x-prefixed hex string
Security Warning: Never commit private keys to version control. Use environment variables or secure configuration management.

​
MAINNET_RPC_URL

  • Type: string
  • Default: "https://sei-mainnet.g.alchemy.com/v2/aRCQx4oOIXZBozWxyx6QG4ltOpRiMMMu"
  • Description: Custom RPC endpoint for Sei mainnet
  • Options: Any valid RPC URL

​
TESTNET_RPC_URL

  • Type: string
  • Default: "https://sei-testnet.g.alchemy.com/v2/aRCQx4oOIXZBozWxyx6QG4ltOpRiMMMu"
  • Description: Custom RPC endpoint for Sei testnet
  • Options: Any valid RPC URL

​
DEVNET_RPC_URL

  • Type: string
  • Default: "https://sei-devnet.g.alchemy.com/v2/aRCQx4oOIXZBozWxyx6QG4ltOpRiMMMu"
  • Description: Custom RPC endpoint for Sei devnet
  • Options: Any valid RPC URL

​
PATH

  • Type: string
  • Default: System PATH
  • Description: Override PATH to specify Node.js version (useful for troubleshooting)
  • Options: Custom PATH string

Need Help?

Having issues? Check our comprehensive troubleshooting guide for solutions to common problems.

​
Security Best Practices

Test Wallet Only

Use a dedicated wallet for testing, not your main holdings

Minimal Funds

Keep only small amounts needed for testing transactions

Secure Storage

Never commit private keys to version control

Regular Rotation

Rotate test wallet keys periodically