A One-Minute Guide to HTTP 402 Payment Required Protocol, Participate in the WEEX Exchange x402 Eco Week Event

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x402 is redefining the next-generation payment protocol for decentralized network value transfer. Learn about the origin of x402 and its profound impact on DeFi and the payment industry. Participate in the WEEX x402 Ecosystem Week event before November 4, 2025, to win rewards of up to $115.

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For decades, the internet has relied on the foundational system of HTTP status codes to support digital interactions. However, there is one status code, "HTTP 402: Payment Required," that has never been truly activated since its inception. Today, Coinbase has revitalized it by embedding on-chain payments directly into the HTTP layer through the open payment protocol x402.

What is x402?

x402 is an open, internet-native payment protocol that leverages the long-dormant HTTP 402 "Payment Required" status code to embed programmable on-chain payments directly into regular HTTP request interactions.

It allows clients—especially autonomous AI agents or machine-to-machine callers—to automatically discover pricing, submit encrypted payment credentials in the request header (X-PAYMENT header), and receive the paid-for resource within the same request/response flow.

The protocol is blockchain-agnostic but commonly used with stablecoins (such as USDC) and custodial "Facilitator" services to validate on behalf of the seller and settle payments.

This means machines can autonomously pay for data, computations, or usage of models just like browsing a webpage. By extending payment capability to the most fundamental internet protocol, x402 effectively turns the internet into a programmable economy.

x402 was developed and open-sourced by Coinbase to address the actual need for metered billing when machines interact with APIs, models, and data. Coinbase has released related documentation and reference implementations on GitHub and its developer platform, collaborating with ecosystem partners to drive adoption. By the end of 2025, Coinbase and Cloudflare announced the establishment of the x402 Foundation to coordinate standards, tools, and promote broader industry adoption.

The Impact of x402 on the Industry

For payments, x402 is to payment as HTTPS is to data: a simple yet foundational upgrade.

It unlocks true machine-to-machine (M2M) commerce, enabling every API call, data access, or model inference to be fairly and automatically monetized.

● For enterprises: Micropayments and API usage-based billing models can operate at scale.

● For Developers: No need for complex billing infrastructure.

● For AI: It's the missing piece—enabling autonomous agents to not only process information but also pay for information.

This transformation could reshape multiple industries, where data providers can charge on-demand, AI models can offer tiered pricing based on accuracy, and web services can enable temporary access through a token mechanism without human intervention. As more systems adopt x402, the boundary between information and value will gradually blur—a "self-paying internet" is taking shape.

x402 addresses a real pain point: machines (AI agents, IoT devices, serverless functions) cannot easily use human-centric payment methods (such as credit cards, OAuth subscriptions, or invoices). By making payments a first-class primitive of HTTP, x402 enables a whole new business and technical paradigm:

● Micro-payments and Pay-per-Call: Services can precisely charge based on usage (e.g., per inference, data query, document access) without subscription overhead.

● Agentic Commerce & Composability: Autonomous agents can autonomously discover, compare, and pay for third-party plugins or APIs, enabling richer smart agent functionalities and multi-agent markets (Google's AP2/Agent Payments has explored interoperability with x402).

● Lower Entry Barriers: No need to register accounts, link bank cards, or go through cumbersome billing processes, more suitable for pay-as-you-go scenarios, accelerating developer conversions.

● Operationality and Trust Models: Facilitators (including Coinbase's custody services) can streamline settlement and compliance processes (such as KYT, OFAC screening), but at the same time introduce a "trusted service" model, where teams need to weigh in between this and self-built solutions.

The Future Vision of x402

Imagine an internet where the economic layer and the data layer have no friction: AI agents can instantly access paywalled knowledge bases, compute markets price inference based on latency and accuracy, micro-sensors can pay for edge computing on demand.

In such a world:

● The Microservice Market thrives (Discovery + Real-time Settlement)

● Models can be rented out by the second or by token

● Value transfer has composability (Agent A pays Model B, Model B pays Data Source C)

All of this is done through standard HTTP semantic coordination.

x402 is a step toward this future: it does not create a new consensus mechanism or token but provides a standardized machine-readable format for the internet to express "This resource's price is X" and receive a final on-chain payment credential. If widely adopted, x402 will redefine the pricing and consumption of digital goods and computing power.

New User Special, x402 Ecosystem Week

To celebrate the rise of this new payment paradigm, WEEX, one of the world's leading cryptocurrency exchange platforms, is officially launching the x402 Ecosystem Week—a limited-time event designed for new users to usher in the future of on-chain payments.

Event Duration: October 24, 2025 - November 4, 2025 (UTC+8)

New users can earn rewards of up to $115 USDT by completing a series of simple tasks:

● Activity 1: Net Deposit ≥ 100 USDT, Reward 8 USDT During the event, new users who net deposit ≥100 USDT or an equivalent amount of any of the event tokens (SANTA, AURABASE, PAYAI, MRDN) will receive an 8 USDT reward.

● Activity 2: Complete First Spot Trade, Reward 7 USDT During the event, new users who make their first trade with any of the event tokens (SANTA, AURABASE, PAYAI, MRDN) and achieve a spot trading volume of 100 USDT will receive a 7 USDT reward.

● Activity 3: Daily Trading Check-In, Easily Earn 100 USDT During the event, with no restrictions on trading tokens, new users who accumulate a daily contract trading volume ≥ 500 USDT will be considered as successfully checking in. Users who successfully check-in will receive 1 mystery box (5~10 USDT contract trial fund) and can check-in up to once per day. Users can earn a maximum of 100 USDT per person during the event, and rewards will be distributed uniformly after the event ends.

● Activity 4: Reward Redemption Criteria During the event, users must complete activities one, two, and three in order to unlock all corresponding rewards!