X402DIRECT
Direct payments without platform risk.
Customers pay vendors directly. No processor, no shutdown risk, no surprise holds.
Pay anyone, anywhere
Direct on-chain payments remove borders, intermediaries, and platform shutdown risk.
Direct + Flexible Payments
- Payments go directly from customer to vendor with no payment processing intermediary.
- Payor can submit the payment to the blockchain or the vendor can submit it.
- Ultralow transaction costs with complete flexibility on who pays those costs.
Ultimate Control
- Funds cannot be transferred without approval from the payor wallet.
- Payor wallets set limits on the amount spent per day, week, and total.
- Wallet owners can temporarily delegate spend permissions while keeping strict caps.
Built for Agents
- Built for agentic payments and throwaway wallets for safer online shopping.
- Link wallets to AgentPMT for gas sponsorship, marketplace access, and MCP integration.
Implement X402DIRECT
Add direct, verifiable stablecoin payments to your API or checkout flow with minimal integration work.
Connect Your Wallet
Connect a wallet to control spending limits, approve payments, and keep full custody of your funds.
Connect Your AI Agent
Use sponsored gas, an MCP tool for X402DIRECT spending, and AgentPMT integrations to power autonomous payments.
Add the Ding extension to your browser and make easy X402DIRECT payments at any site that accepts it.
Simple, Secure, Direct
Client Requests Protected Resource
Server returns 402 Payment Required with unique nonce (integer), payment options (chain, token, amount), and any additional required fields
Client Executes Payment
Client calls executePayment() on UPC contract with nonce, transferring stablecoins to merchant
Contract Emits Event
Smart contract emits PaymentExecuted event on-chain for cryptographic verification
Client Submits Proof & Gets Access
Client submits transaction hash + nonce + additional fields. Server verifies payment on-chain and grants instant access
// Payment verification is trustless
verifyPayment(txHash, nonce, paymentOption)
Built for Cutting-Edge Chains
Supports modern blockchains with CAIP standard compliance
Base
Layer 2 for Ethereum
Base Sepolia
Testnet environment
ARC Testnet
Testnet environment
Live x402Direct Contracts
Current chain configuration, UPC addresses, and on-chain fee parameters for this deployment.
Key Protocol Features
Built for the era of AI agents and autonomous payments
Integer Nonces
Unique integer payment identifiers prevent replay attacks and ensure one-time use
CAIP Standard
Chain-agnostic using CAIP-2 and CAIP-10 for universal blockchain addressing
Additional Fields
Support for vendor-specific fields like userEmail, userName for personalization
AI Agent Ready
Machine-readable HTTP 402 responses for autonomous payment execution
Stablecoin Native
Built for USDC, USDT, and other stablecoins with precise amount handling
Instant Verification
On-chain payment verification in seconds on modern high-speed blockchains
Contributors
Apoth3osis.io and AgentPMT.com are collaborating to build X402DIRECT and its ecosystem.
Apoth3osis.io
Apoth3osis.io focuses on mathematical research, cryptography, mathematical proofs, and AI research.
Visit Apoth3osis.io ->AgentPMT.com
AgentPMT.com brings X402DIRECT into production with programmable USDC wallets, controlled budgets, and a marketplace where agents can purchase tools and services with verified on-chain payments.
Visit AgentPMT.com ->Protocol Overview
Simple HTTP 402 Payment Required responses with on-chain verification
// 402 Payment Required Response
{
"x402version": "direct.1.0.0",
"nonce": 1234567890,
"description": "Premium API Access",
"resource": "/api/premium/data",
"accessMethod": "GET",
"additionalRequired": {
"userEmail": "user@example.com"
},
"paymentOptions": [{
"id": "po_base_usdc",
"payToAddress": "eip155:8453:0x742d35Cc...",
"assetAddress": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"amountRequired": 1000000, // 1 USDC
"description": "1 USDC on Base"
}]
}