All About x402

Explore the x402 protocol from its core architecture and extensions to the future of agentic commerce. This analysis addresses key market questions, identifies ecosystem value-capture layers, and examines how big tech is strategically responding. Contributions from an x402 co-author and key ecosystem participants offer firsthand perspectives on the opportunities and challenges ahead for x402 and agentic commerce.

Sep 15, 2026

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Four Pillars

Jun

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x402 is an open payment specification that enables agents to discover prices and pay for resources on the web. It connects the presentation of payment terms with authorization, verification, and settlement, while separating transport, payment schemes, and networks to support different environments. Coinbase released the protocol in 2025, and its transfer to the Linux Foundation and the launch of the x402 Foundation were announced on April 2, 2026.
The initial opportunity lies in the T3 market, where agents directly purchase the APIs, data, and computing resources needed to achieve their goals. As T1, where people give final approval, and T2, where agents select and execute purchases based on users’ preferences and purchase conditions, expand, the benefits of greater autonomy may first be demonstrated in low-value, high-frequency transactions for digital resources. The author’s scenarios for AI-mediated B2B commerce in 2028 yield annual x402 payment volumes of approximately $0.19 trillion to $1.92 trillion, with T3 accounting for roughly 96% under the assumed payment shares.
The revenue opportunities created by x402 adoption differ across layers. Stablecoin issuers can earn revenue from net increases in circulating balances, blockchains from settlement transactions, and facilitators from paid processing volume. Wallets can capture value by managing fund and settlement routes, while discovery and routing services can do so through supplier selection and order allocation.
The open-source community and existing platforms can reinforce one another’s development. The community advances shared specifications and capabilities, while Cloudflare, AWS, Google, and Fastly integrate them into their existing customers’ workflows. Further ecosystem development requires more services that generate repeat purchases, alongside a more refined operating framework that clearly allocates authority and responsibility for failure costs among wallets, sellers, and facilitators.
Contributors: Kevin Leffew (x402 Co-author, Coinbase), Richard Widmann (Global Head of Strategy, Web3 and Digital Assets, Google), Raj Parekh (Head of Payments and AI, Monad Foundation), Shafu (Agentic Commerce, Circle), Jing Yi Tan (a.k.a. Cookies, AI Ecosystem, Monad Foundation), Michael Blau (Founder, dripstack.com), Rish (AI, Solana), Jay Yu, Jesse Chung(Co-Founnder Seal).

The author of this report may have personal holdings or financial interests in assets or tokens discussed herein. However, the author affirms that no transactions have conducted using material non-public information obtained in the course of research or drafting. This report is intended solely for general information purposes and does not constitute legal, business, investment, or tax advice. It should not be used as a basis for making any investment decisions or as guidance for accounting, legal, or tax matters. Any references to specific assets or securities are made for informational purposes only and should not be construed as an offer, solicitation, or recommendation to invest. The opinions expressed herein are those of the author and may not reflect the views of any affiliated institutions, organizations, or individuals. The opinions and analyses expressed herein are subject to change without prior notice. In addition, beyond the individual disclosures included in each report, Four Pillars, may hold existing or prospective investments in some of the assets or protocols discussed herein. Furthermore, FP Validated, a division of Four Pillars, may already be operating as a node in certain networks or protocols discussed herein or may do so in the future. Please see below links in the footer for FP Validated's participating network disclosures and for broader disclosure details.

All About x402

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