# GateX402 — Full Documentation for LLMs

> GateX402 is an API monetization platform enabling developers to accept USDC crypto micropayments for their APIs using the x402 HTTP payment protocol. Supports Base and Solana networks with instant setup, 1% platform fee, and daily automated payouts.

## What is GateX402?

GateX402 is a gateway service for monetizing APIs with cryptocurrency micropayments. API providers register their endpoints on the platform, set per-route pricing in USDC, and GateX402 handles payment verification, collection, and daily payouts.

The platform is purpose-built for the AI agent economy — where autonomous AI agents need to discover, evaluate, and pay for API services programmatically without human intervention.

## How the x402 Protocol Works

The x402 protocol uses the HTTP 402 Payment Required status code for micropayments:

1. **Request**: An AI agent or consumer sends an HTTP request to a GateX402-proxied API endpoint.
2. **Challenge**: The gateway responds with HTTP 402 Payment Required, including payment details in headers:
   - `X-Payment-Required`: Amount in USDC
   - `X-Payment-Network`: Target blockchain (base or solana)
   - `X-Payment-Address`: Provider's wallet address
   - `X-Payment-Facilitator`: Facilitator URL for payment verification
3. **Payment**: The caller constructs and signs a USDC transfer transaction.
4. **Verification**: The facilitator verifies the payment on-chain.
5. **Forwarding**: Upon verification, the gateway forwards the original request to the provider's API.
6. **Response**: The API response is returned to the caller.

## Supported Networks

### Base (Ethereum L2)
- Network: Base Mainnet
- Currency: USDC (native)
- Settlement: Near-instant (~2 seconds)
- Gas costs: Very low (<$0.01)

### Solana
- Network: Solana Mainnet
- Currency: USDC (SPL Token)
- Settlement: Near-instant (~0.4 seconds)
- Gas costs: Minimal (~$0.001)

## Pricing Model

- **Platform Fee**: 1% of each transaction
- **Provider Revenue**: 99% of each transaction goes directly to the provider
- **Minimum Price**: $0.001 per request
- **Maximum Price**: No limit
- **Payouts**: Daily automated payouts to provider wallet addresses
- **No Monthly Fees**: No subscription or platform fees beyond the 1% transaction fee

## For API Providers

### Getting Started
1. Create an account at https://gatex402.dev/signup
2. Connect your wallet (Base or Solana)
3. Add your API domain
4. Configure per-route pricing
5. Point your DNS to the GateX402 gateway
6. Start earning USDC on every API call

### What You Can Monetize
- REST APIs (GET, POST, PUT, DELETE)
- AI/ML inference endpoints
- Data feeds and market data
- Content generation APIs
- Any HTTP-based service

## For AI Agents (Consumers)

### Discovering APIs
The Bazaar Discovery marketplace at https://gatex402.dev/discover provides a machine-readable catalog of all x402-enabled APIs. Each listing includes:
- API name and description
- Endpoint URL
- Pricing (USDC per request)
- HTTP method
- Supported network(s)
- Input schema (when available)
- Output example (when available)
- x402 protocol version

### Consuming a Paid API
To consume an x402-enabled API programmatically:

1. Send a request to the API endpoint
2. Receive the 402 response with payment details
3. Construct a USDC payment transaction for the specified amount
4. Sign and submit the transaction
5. Include the transaction hash in the `X-Payment-Proof` header
6. Resend the original request with the proof header
7. Receive the API response

### Machine-Readable Discovery
- **Bazaar API**: The `/discover` page serves structured API catalog data
- **JSON-LD**: All API listings include Schema.org WebAPI structured data
- **llms.txt**: This file and the summary version at `/llms.txt`
- **ai-plugin.json**: OpenAI-compatible manifest at `/.well-known/ai-plugin.json`

## Agent API Reference (Programmatic Management)

AI agents can autonomously provision, manage, and monetize their own APIs without the GateX402 dashboard.

### 1. Self-Provisioning Handshake
1. **Challenge**: `POST /agent/nonce` with `{ "wallet_address": "0x...", "action": "provision" }`.
2. **Sign**: Sign the returned `message` using your private key (EIP-191).
3. **Provision**: `POST /agent/provision` with the `signature`, `nonce`, and API config.
4. **Token**: Securely store the returned `management_token` (prefix: `gx4_mgmt_`).

### 2. Management Endpoints (Bearer Token Required)
| Action | Method | Path | Description |
|--------|--------|------|-------------|
| List APIs | GET | `/agent/apis` | Returns array of provisioned APIs |
| Balance | GET | `/agent/payout/balance` | Real-time USDC earnings balance |
| Withdraw | POST | `/agent/payout/withdraw` | Instant payout to registered wallet |
| Set Wallet | PATCH | `/agent/wallet` | Change the payout destination address |
| Rotate Key | POST | `/agent/key/rotate` | Swap current token for a new one |

### 3. Implementation Example (Node.js)
```typescript
const { nonce, message } = await fetch('https://api.gatex402.dev/agent/nonce', {
  method: 'POST',
  body: JSON.stringify({ wallet_address, action: 'provision' })
}).then(r => r.json());

const signature = await wallet.signMessage(message);

const { management_token } = await fetch('https://api.gatex402.dev/agent/provision', {
  method: 'POST',
  body: JSON.stringify({ wallet_address, signature, nonce, api_name: "Agent API", routes: [...] })
}).then(r => r.json());
```

For full specifications, refer to [AGENT_API_REFERENCE.md](https://gatex402.dev/AGENT_API_REFERENCE.md).

## Ecosystem Compatibility

- **Coinbase Agentic Wallet**: Fully compatible. Use the `awal` CLI for gasless payments and session-level spending limits.
- **x402 Protocol**: Native enforcement. Agents must handle 402 responses and include `payment-signature` on retry.
- **skills.sh**: Ready for registration. Use `npx skills add gatex402` once published.

## Key URLs

| Resource | URL |
|----------|-----|
| Homepage | https://gatex402.dev |
| API Discovery | https://gatex402.dev/discover |
| Sign Up | https://gatex402.dev/signup |
| Login | https://gatex402.dev/login |
| Contact | https://gatex402.dev/contact |
| LLMs Summary | https://gatex402.dev/llms.txt |
| AI Plugin Manifest | https://gatex402.dev/.well-known/ai-plugin.json |
| Sitemap | https://gatex402.dev/sitemap.xml |
| Robots | https://gatex402.dev/robots.txt |
| X/Twitter | https://x.com/gatex402 |
| LinkedIn | https://linkedin.com/company/gatex402 |

## FAQ

**Q: What is x402?**
A: x402 is an open HTTP payment protocol that uses the HTTP 402 Payment Required status code to enable per-request micropayments with USDC stablecoin.

**Q: Which blockchains are supported?**
A: GateX402 currently supports Base (Ethereum L2) and Solana.

**Q: What currency is used for payments?**
A: All payments are in USDC, a USD-pegged stablecoin. No price volatility.

**Q: How much does GateX402 charge?**
A: GateX402 charges a 1% fee per transaction. There are no subscription fees or monthly charges.

**Q: How do I get paid?**
A: Payouts are automated daily to your connected wallet address.

**Q: Can AI agents use GateX402-powered APIs?**
A: Yes. GateX402 is built specifically for AI agent consumption. The x402 protocol is designed for programmatic, machine-to-machine payments.

**Q: How do I discover available APIs?**
A: Visit https://gatex402.dev/discover to browse the Bazaar Discovery marketplace, or parse the machine-readable structured data on the page.