// Check if running inside Gao Browser  
const isGaoBrowser = typeof window.gao !== 'undefined';  
  
if (isGaoBrowser) {  
  // Can use native .gao resolution and x402  
  const identity = await window.gao.domain.resolve('merchant.gao');  
} else {  
  // Fallback to standard Web3 or gateway URL  
}

// Resolve a .gao domain  
const identity = await window.gao.domain.resolve('merchant.gao');  
// Returns: { domain, trust_level, wallet, payment_proxy, content, agents }  
  
// Resolve wallet for payment  
const address = await window.gao.domain.resolveWallet('merchant.gao', 'base');  
// Returns proxy address for private domains, real address for public  
  
// Get trust badge data  
const badge = await window.gao.domain.getTrustBadge('merchant.gao');  
// Returns: { level: 2, label: "Business Verified", color: "#2563EB", icon: "✅" }

// Request payment via the browser's payment flow  
const receipt = await window.gao.payment.request({  
  to:            'merchant.gao',  
  amount:        '50.00',  
  token:         'USDC',  
  chain:         'base',  
  memo:          'Order #1042',  
});  
  
// receipt is null if user cancelled  
if (receipt) {  
  console.log(receipt.receipt_id);    // rcpt_pay_abc123  
  console.log(receipt.tx_hash);       // on-chain tx  
}

// Express.js example  
app.get('/api/premium', (req, res) => {  
  const proof = req.headers['x-gao-payment-proof'];  
  
  if (!proof) {  
    return res.status(402).json({  
      payee_domain: 'myapi.gao',  
      amount:       '0.01',  
      currency:     'USDC',  
      network:      'base',  
      expires_in:   300,  
    });  
  }  
  
  // Validate proof (see Gao Payment Layer 4 docs)  
  validateAndServe(req, res);  
});

// Invoke an agent on the current domain  
const result = await window.gao.agent.invoke({  
  agentDomain: 'assistant.merchant.gao',  
  action:      'schedule_appointment',  
  input:       { date: '2026-04-20', time: '14:00', service: 'manicure' },  
});  
  
// result is null if user denied the approval  
if (result) {  
  console.log(result.output);   // agent output  
  console.log(result.receipt);  // GAR receipt from Layer 8  
}

const BADGE_SPECS = {  
  0: { icon: '⚠️', label: 'Unverified',        color: '#F59E0B' },  
  1: { icon: '✓',  label: 'Identity Verified',  color: '#6B7280' },  
  2: { icon: '✅', label: 'Business Verified',   color: '#2563EB' },  
  3: { icon: '🏛', label: 'Official',           color: '#D97706' },  
};

import { useTrustBadge } from '@gao-internet/sdk/react';  
  
function DomainBadge({ domain }: { domain: string }) {  
  const { badge, loading } = useTrustBadge(domain);  
  
  if (loading) return <span>Verifying {domain}…</span>;  
  
  return (  
    <div className={`trust-badge level-${badge.level}`}  
         style={{ color: badge.color }}>  
      <span>{badge.icon}</span>  
      <span>{domain}</span>  
      {badge.displayName && <span>{badge.displayName}</span>}  
    </div>  
  );  
}

---

### Resolver Integration

Community resolvers must conform to the `GI-DOMAIN-RESOLVER/1.0` specification. See Anchor Contract & Conformance for the full conformance test suite.

The browser queries resolvers in this priority order:

1.  Gao official resolver (default)
    
2.  User-configured resolver (settings → resolver)
    
3.  Community resolvers (automatic fallback)
    

To register as a community resolver:

// Available in Gao Browser extension context  
chrome.gao.domain.onResolution.addListener((event) => {  
  console.log(event.domain, event.trustLevel);  
});  
  
chrome.gao.payment.onReceipt.addListener((receipt) => {  
  console.log('Payment settled:', receipt.receipt_id);  
});