# Configuration
Universal Crypto MCP can be configured through environment variables, a config file, or CLI arguments.
## Environment Variables
### Core Settings
| Variable | Description | Default |
|----------|-------------|---------|
| `NODE_ENV` | Environment mode | `production` |
| `LOG_LEVEL` | Logging level (DEBUG, INFO, WARN, ERROR) | `INFO` |
| `MCP_TRANSPORT` | Transport mode (stdio, http, sse) | `stdio` |
| `MCP_PORT` | HTTP/SSE server port | `3000` |
### API Keys
| Variable | Description | Required For |
|----------|-------------|--------------|
| `COINGECKO_API_KEY` | CoinGecko Pro API key | Enhanced market data |
| `BINANCE_API_KEY` | Binance API key | Trading tools |
| `BINANCE_API_SECRET` | Binance API secret | Trading tools |
| `BINANCE_US_API_KEY` | Binance US API key | US trading |
| `BINANCE_US_API_SECRET` | Binance US API secret | US trading |
| `CRYPTOPANIC_API_KEY` | CryptoPanic API key | News tools |
| `ETHERSCAN_API_KEY` | Etherscan API key | Contract verification |
| `INFURA_API_KEY` | Infura API key | RPC fallback |
| `ALCHEMY_API_KEY` | Alchemy API key | RPC fallback |
### x402 Payment Settings
| Variable | Description | Default |
|----------|-------------|---------|
| `X402_PRIVATE_KEY` | EVM private key for payments | - |
| `X402_CHAIN` | Default chain | `arbitrum` |
| `X402_MAX_AMOUNT` | Maximum payment amount | `1.0` |
| `X402_AUTO_PAY` | Enable automatic payments | `false` |
### Wallet Settings
| Variable | Description | Default |
|----------|-------------|---------|
| `PRIVATE_KEY` | EVM wallet private key | - |
| `MNEMONIC` | HD wallet mnemonic phrase | - |
| `RPC_URL` | Custom RPC endpoint | Chain default |
## Configuration File
Create a `.universal-crypto-mcp.json` file in your project root or home directory:
```json
{
"transport": "stdio",
"logLevel": "INFO",
"modules": {
"trading": {
"enabled": true,
"exchanges": ["binance", "binance-us"]
},
"marketData": {
"enabled": true,
"providers": ["coingecko", "dexpaprika"]
},
"defi": {
"enabled": true,
"protocols": ["aave", "uniswap", "compound"]
},
"wallets": {
"enabled": true,
"chains": ["ethereum", "arbitrum", "base", "polygon"]
},
"payments": {
"enabled": true,
"x402": {
"chain": "arbitrum",
"maxAmount": "1.0",
"autoPay": false
}
}
},
"rpc": {
"ethereum": "https://eth.llamarpc.com",
"arbitrum": "https://arb1.arbitrum.io/rpc",
"base": "https://mainnet.base.org",
"polygon": "https://polygon-rpc.com"
}
}
```
## CLI Arguments
Override settings via command line:
```bash
# Transport mode
npx @nirholas/universal-crypto-mcp --http --port 8080
# Log level
npx @nirholas/universal-crypto-mcp --log-level DEBUG
# Enable specific modules
npx @nirholas/universal-crypto-mcp --modules trading,market-data
# Custom config file
npx @nirholas/universal-crypto-mcp --config ./my-config.json
```
## Priority Order
Configuration is applied in this order (later overrides earlier):
1. Default values
2. Configuration file
3. Environment variables
4. CLI arguments
## Module-Specific Configuration
### Trading Module
```json
{
"modules": {
"trading": {
"enabled": true,
"exchanges": ["binance"],
"sandbox": false,
"defaultPairs": ["BTC/USDT", "ETH/USDT"]
}
}
}
```
### DeFi Module
```json
{
"modules": {
"defi": {
"enabled": true,
"protocols": ["aave", "uniswap", "compound"],
"slippageTolerance": 0.5,
"gasMultiplier": 1.2
}
}
}
```
### Wallet Module
```json
{
"modules": {
"wallets": {
"enabled": true,
"chains": ["ethereum", "arbitrum"],
"confirmations": 1,
"gasStrategy": "fast"
}
}
}
```
## Security Best Practices
### Never Commit Secrets
Add to your `.gitignore`:
```gitignore
.env
.env.local
*.key
*-key.json
```
### Use Environment Variables
Store sensitive data in environment variables, not config files:
```bash
export X402_PRIVATE_KEY="0x..."
export BINANCE_API_KEY="..."
export BINANCE_API_SECRET="..."
```
### Limit Permissions
When using API keys:
- Enable only required permissions
- Use IP whitelisting when available
- Set spending limits for exchange APIs
### Test with Small Amounts
Always test with small amounts before enabling larger transactions:
```json
{
"modules": {
"payments": {
"x402": {
"maxAmount": "0.01"
}
}
}
}
```
## Next Steps
- [First Tool](first-tool.md) - Use your first crypto tool
- [Deployment](deployment.md) - Deploy to production
