{
  "openapi": "3.1.0",
  "info": {
    "title": "0xGate Zero-KYC Crypto Payment Gateway API",
    "version": "1.0.0",
    "description": "Permissionless, zero-KYC multi-chain USDT & USDC payment gateway API for e-commerce stores, high-risk merchants, and autonomous AI agents. Supports TRC20 (Tron), BSC (BEP20), Polygon, and Ethereum (ERC20) with cross-chain EVM mistake recovery and exchange fee slippage protection.",
    "contact": {
      "name": "0xGate Protocol",
      "email": "admin@0xgate.org",
      "url": "https://0xgate.org"
    }
  },
  "servers": [
    {
      "url": "https://0xgate.org",
      "description": "0xGate Production Cloud Gateway"
    }
  ],
  "paths": {
    "/api/auth/register": {
      "post": {
        "operationId": "registerMerchantAccount",
        "summary": "Register an anonymous Zero-KYC merchant account in 1 API call",
        "description": "Creates a live merchant account with zero identity verification. Requires only a username, password, and crypto payout wallet address.",
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["username", "password", "payout_type", "payout_network", "payout_address"],
                "properties": {
                  "username": {
                    "type": "string",
                    "description": "Unique merchant identifier used in payment links (e.g. apex_store)"
                  },
                  "password": {
                    "type": "string",
                    "description": "Merchant password (minimum 8 characters)"
                  },
                  "payout_type": {
                    "type": "string",
                    "enum": ["TOKEN", "COIN"],
                    "default": "TOKEN"
                  },
                  "payout_network": {
                    "type": "string",
                    "enum": ["TRC20", "BSC", "POLYGON", "ERC20"],
                    "description": "Destination blockchain network for payouts"
                  },
                  "payout_address": {
                    "type": "string",
                    "description": "Merchant's personal wallet address (0x... for EVM or T... for Tron)"
                  },
                  "webhook_url": {
                    "type": "string",
                    "description": "Optional URL to receive instant POST webhook notifications when invoices are paid"
                  }
                }
              }
            }
          }
        },
        "responses": {
          "201": {
            "description": "Merchant registered successfully"
          }
        }
      }
    },
    "/pay/new": {
      "get": {
        "operationId": "createCheckoutRedirectInvoice",
        "summary": "Generate a live crypto payment invoice via URL redirect",
        "description": "Creates a new single-use BIP44 deposit address and redirects the buyer to the hosted checkout page. Can be shared directly as a payment link.",
        "parameters": [
          {
            "name": "merchant",
            "in": "query",
            "required": true,
            "schema": { "type": "string" },
            "description": "Merchant username or sub-profile identifier"
          },
          {
            "name": "amount",
            "in": "query",
            "required": true,
            "schema": { "type": "number" },
            "description": "Invoice amount in USD (e.g. 49.99)"
          },
          {
            "name": "website",
            "in": "query",
            "required": false,
            "schema": { "type": "string" },
            "description": "Store or service name displayed on checkout"
          },
          {
            "name": "ref",
            "in": "query",
            "required": false,
            "schema": { "type": "string" },
            "description": "Unique order reference ID to prevent duplicate payments"
          },
          {
            "name": "network",
            "in": "query",
            "required": false,
            "schema": { "type": "string", "enum": ["TRC20", "BSC", "POLYGON", "ERC20"] },
            "description": "Optional pre-selected blockchain network"
          },
          {
            "name": "currency",
            "in": "query",
            "required": false,
            "schema": { "type": "string", "enum": ["USDT", "USDC"] },
            "description": "Optional pre-selected stablecoin"
          }
        ],
        "responses": {
          "302": {
            "description": "Redirects to /pay/{invoice_id}"
          }
        }
      }
    },
    "/api/public/pay/{id}": {
      "get": {
        "operationId": "getInvoiceStatus",
        "summary": "Get real-time on-chain payment status and deposit address for an invoice",
        "parameters": [
          {
            "name": "id",
            "in": "path",
            "required": true,
            "schema": { "type": "integer" },
            "description": "Invoice ID"
          }
        ],
        "responses": {
          "200": {
            "description": "Invoice details and live status (PENDING, PAID, EXPIRED, UNDERPAID)"
          }
        }
      }
    },
    "/api/public/pay/{id}/select-method": {
      "post": {
        "operationId": "selectInvoicePaymentMethod",
        "summary": "Lock a specific blockchain network and stablecoin for a pending invoice",
        "parameters": [
          {
            "name": "id",
            "in": "path",
            "required": true,
            "schema": { "type": "integer" }
          }
        ],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["network", "crypto_currency"],
                "properties": {
                  "network": { "type": "string", "enum": ["TRC20", "BSC", "POLYGON", "ERC20"] },
                  "crypto_currency": { "type": "string", "enum": ["USDT", "USDC"] }
                }
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "Returns the derived deposit address for the selected network"
          }
        }
      }
    }
  }
}