What is x402Direct?
The open payment protocol enabling AI agents to make autonomous purchases on the internet.
Internet-Native Micropayments for the Agentic Economy
x402 is an open payments protocol that activates the HTTP 402 “Payment Required” status code to enable instant, blockchain-based payments for web resources and APIs. Our implementation uses the x402Direct schema, which requires no separate payment processor or third-party intermediaries. Built on permissionless blockchain infrastructure, x402Direct eliminates traditional payment inefficiencies by enabling direct buyer-to-vendor transfers via smart contracts.
How x402Direct Works
Request & Nonce Generation
A buyer (AI agent or user) wants to make a payment. The vendor provides a unique nonce with payment details including amount, currency (USDC), and the smart contract address.
Direct Payment via Smart Contract
The buyer sends a message to the x402Direct smart contract with the nonce. The smart contract moves funds directly from buyer to vendor on-chain and emits a transaction event with a unique transaction ID.
Payment Proof Submission
The buyer requests access again, providing both the nonce and the transaction ID from the smart contract. The vendor receives this proof of payment via query parameter or HTTP header.
Verification & Access Granted
The vendor checks the smart contract event to confirm the transaction ID corresponds to the nonce and payment was received. Upon verification, access is granted.
Why x402 Matters for AI Agents
Autonomous Commerce
AI agents discover payment requirements, execute blockchain transactions, and complete purchases without human intervention. No API keys, accounts, or pre-existing relationships required.
Global & Permissionless
Available worldwide without costly currency conversions or access to traditional financial rails. Any agent, anywhere, can transact instantly using cryptocurrency.
Micropayment Economics
Payments via x402Direct are very inexpensive. True pay-per-use pricing becomes practical without the burden of traditional payment processing fees.
Direct Settlement
Payments move directly from buyer to vendor via smart contract in seconds on Layer-2 networks like Base. No third-party processors, no chargebacks, no delays.
Real-World Use Cases
Premium Content & News
Publishers gate articles behind micropayments. AI agents and readers pay per article rather than committing to full subscriptions.
API Access & Data Feeds
Services charge per API call instead of monthly subscriptions. An agent needing real-time data pays only for specific requests.
Cloud Computing Resources
AI agents autonomously purchase compute time, storage, or GPU cycles on demand. Pay-per-second pricing becomes practical.
E-Commerce & Tool Discovery
An AI shopping assistant browses merchants, compares prices, and completes purchases without pre-configured accounts at each vendor.
Research & Academic Papers
Researchers and AI systems pay per paper access instead of expensive journal subscriptions, democratizing access to scientific knowledge.
Why x402Direct?
The x402Direct schema eliminates intermediaries and provides true peer-to-peer payment capabilities on the blockchain. By using smart contract events and nonce-based verification, the system ensures:
x402direct.org — Official Specification
Complete documentation, technical specifications, and current fee structure for the x402Direct schema.
Visit x402direct.org →Ready to Build with x402?
AgentPMT provides the infrastructure for AI agents to make controlled payments using x402, USDC, and programmable wallets.