U.S.-listed cryptocurrency exchange Coinbase (COIN) has unleashed the latest version of its stablecoin-based payments protocol for AI agents, making it easier to extend and plug in the autonomous payments system, the exchange said in a blogpost Thursday.

The snappily titled x402 V2 moves the AI agentic payments tool on from asking "So what does it actually do" into "Which existing services can we plug it into next," a Coinbase representative said in an email. Specifically, x402 V2 allows developers to combine payments, enable secure wallet access, and add new features via a clean, modular design, Coinbase said.

Earlier this year, Coinbase engineers released the open source autonomous payments protocol x402, and more recently added a discovery layer for AI agents, something like a “Google for agents,” dubbed x402 Bazaar.

In a note attached to the blogpost, Coinbase said x402 V2 expands the protocol beyond single-call, exact payments. “It adds wallet-based identity (skip repaying on every call), automatic API discovery, dynamic payment recipients, support for more chains and fiat via CAIP [Chain Agnostic Improvement Proposals for blockchain interoperability] standards, and a fully modular SDK for custom networks and schemes,” Coinbase said.

It’s all aimed at making x402 “cleaner, more extensible, and future-proof, enabling unified payment models and wallet-based access for agents and humans alike,” the exchange said.