Cardano founder Charles Hoskinson says the network is on the cusp of a significant shift, reacting to news that an HTTP-402–based payments standard—known as “x402”—is being brought to Cardano and integrated with Masumi, an agent-to-agent protocol built atop the chain. “This is very big for Cardano,” Hoskinson wrote on X on October 27, in response to the demo announcement.
The catalyst is a proof-of-concept published by Masumi cofounder Patrick Tobler showing a live x402 “pay-to-access” flow that ends in an on-chain action: a memecoin mint on Cardano. Tobler framed it as a milestone en route to standardizing how autonomous agents and web services exchange value via APIs without log-ins or OAuth.
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“x402 is coming to Cardano (and Masumi)! … The first x402 Proof-Of-Concept Memecoin Mint,” he posted, adding that users can try the demo with 2 USDM for payment and a small amount of ADA for fees—and stressing that the token itself is strictly a technical showcase with “0 future plans.”
What This Means For Cardano
In a series of follow-ups, Tobler described x402 as a revival of the web’s long-dormant HTTP 402 “Payment Required” status code, generalized for modern machine-to-machine commerce. “Built around the HTTP 402 status code, x402 enables users to pay for resources via API without registration, emails, OAuth, or complex signatures,” he wrote, noting that Coinbase developed the protocol and that it is integrated into Google’s Agent Payments Protocol (AP2).
The Masumi implementation pairs that transport-level payment primitive with smart-contract guarantees for identity, refunds, and decision logging—“turning Cardano into the financial backbone of the agent economy,” as he put it.
The demo itself makes the flow concrete. When a user hits the endpoint, the server responds with “402: Payment Required.” The front end prompts a connected Cardano wallet to construct the payment. The payment proof is then transmitted in the 402 header; the server relays it on-chain, waits for finality, and only then returns the protected resource—in this case, minting the demo memecoins. “Please note: This is NOT a real memecoin. It is ONLY a proof-of-concept intended to showcase the technology!” Tobler emphasized.
Context matters for why Hoskinson’s enthusiasm resonated. x402 has been positioned by Coinbase as an “internet-native payment protocol” for AI agents and APIs, with instant, stablecoin-settled micropayments and merchant tooling. Separately, Google introduced AP2 as an open agent-payments layer designed to support multiple rails—including stablecoins—and to standardize authorization and auditability for agentic commerce. An x402 integration at the chain and smart-contract level gives Cardano a clear line into that emerging stack.
The choice of USDM for the demo highlights another Cardano-specific ingredient: a fiat-backed USD stablecoin native to the network, launched by Moneta (formerly Mehen). USDM’s role in the x402 flow is straightforward—precise, low-friction settlement per request—while ADA remains necessary for network fees. For agent-to-agent use cases, the combination is pragmatic: deterministic fees plus dollar-denominated pricing.
Tobler said the team is now drafting the x402 standard for both Cardano and Masumi, and explicitly not limiting the spec to simple address-to-address transfers. “By not only doing Address-To-Address like most other blockchains do but actually writing the standard to work with the Masumi Smart Contract, we’re making our x402 implementation the most powerful one out there,” he wrote.
At press time, ADA traded at $0.6659.
