🚀 After millions of payments on x402, we’re excited to introduce x402 V2. Listening to community feedback, we’re releasing V2 to evolve internet-native payments with greater flexibility and power. What’s new 🧵

First, a big thank you to the x402 community. This update comes after an extensive community feedback period on the proposed spec. Thank you to the builders, researchers, and teams across ecosystems who reviewed early drafts, filed issues, and shared concrete feedback! x402 is stronger because of you. V2 includes updates to the x402 specification, and a major refactor to the reference SDK

→ More payment options (multi-chain + fiat) V2 standardizes network + asset formats so servers can accept stablecoins on a variety of networks, and even fiat, all through the same x402 interface – no custom logic for each network.

→ Extensions V2 introduces the concept of extensions to the x402 standard. Extensions allow for additional optional data to be passed between the client, server, and facilitator in a structured way. This opens the door for identity, multiple mechanisms of discovery, and much more. Extensions give developers the ability to extend x402, without needing to fork away from the main specification.

→ Works across more networks & transports V2 cleanly separates the spec, its SDK, and facilitators, making it easy to plug in new networks, payment schemes, and transports. The protocol is a fit wherever agents operate.

→ Automatic API discovery The new Discovery extension lets facilitators automatically crawl and update pricing/routes. No more stale catalogs; no manual updates.

→ Cleaner HTTP headers Deprecated X-* headers are replaced with modern names: · PAYMENT-REQUIRED · PAYMENT-SIGNATURE · PAYMENT-RESPONSE Better compatibility with proxies, infra, and modern frameworks.

→ Dynamic routing (payTo determined per request) payTo can now be an onchain address, a role like "merchant", or even a callback that chooses the right recipient per request. This enables new use cases like x402-enabled marketplaces, multi-tenant APIs, and multi-chain catalogs.

→ A simpler, modular SDK The SDK now uses a clean plug-in model. You can add new chains, schemes, facilitators, and business rules without touching core code.

→ Backwards compatible v1 apps keep working, while V2 apps get new capabilities. Facilitators advertise both.

Massive shoutout to @carsonroscoe7 @flyingkittans @fabdarice @jamesrobinson50 @wolfmanreder @Jnix2007 and many more who contributed to development, and to everyone in the ecosystem for their feedback and adoption of v1