Configuration

x402proxy uses a simple JSON configuration file to define protected endpoints, pricing, and payment settings.

Config File Structure

The configuration file must be mounted to /app/config.json inside the container (or placed in the project root for local development).

Required Fields

Field	Description	Example
facilitatorUrl	The x402 facilitator URL	"https://x402.org/facilitator"
network	Blockchain network identifier	"base-sepolia"
paymentAddress	Your wallet address to receive payments	"0x5629562956295629562956295629562956295629"
defaultPrice	Default payment price for all routes	"$0.05"
protectedEndpoints	Map of protected endpoints	See below

Protected Endpoints

The protectedEndpoints object maps endpoint definitions to their configuration:

{
  "protectedEndpoints": {
    "GET /cat": {
      "forwardTo": "https://api.thecatapi.com/v1/images/search"
    },
    "GET /dog": {
      "price": "$0.10",
      "forwardTo": "https://api.thedogapi.com/v1/images/search"
    }
  }
}

Endpoint Format

• Method and Path: "METHOD /path" (e.g., "GET /cat", "POST /api/data")

• forwardTo: The URL to proxy requests to (required if you want to proxy)

• price: Optional per-route price (overrides defaultPrice)

Pricing

Global Pricing

Set a default price that applies to all endpoints:

{
  "defaultPrice": "$0.05"
}

Per-Route Pricing

Override the default price for specific endpoints:

{
  "protectedEndpoints": {
    "GET /premium": {
      "price": "$0.50",
      "forwardTo": "https://api.example.com/premium"
    }
  }
}

Complete Example

{
  "facilitatorUrl": "https://x402.org/facilitator",
  "network": "base-sepolia",
  "paymentAddress": "0x5629562956295629562956295629562956295629",
  "defaultPrice": "$0.05",
  "protectedEndpoints": {
    "GET /cat": {
      "forwardTo": "https://api.thecatapi.com/v1/images/search"
    },
    "GET /dog": {
      "price": "$0.10",
      "forwardTo": "https://api.thedogapi.com/v1/images/search"
    },
    "GET /fact": {
      "price": "$0.15",
      "forwardTo": "https://catfact.ninja/fact"
    }
  }
}

Network Options

Common network identifiers:

• "base-sepolia" - Base Sepolia testnet

• "base" - Base mainnet

• "ethereum" - Ethereum mainnet

• "sepolia" - Ethereum Sepolia testnet

• "solana" - Solana mainnet

Check with your x402 facilitator for supported networks.