x402, AP2, Agent Pay: Three Standards, One Question — Who Becomes TCP/IP?

Three major standards are advancing in parallel — and they actually solve three different layers of the problem.

x402: minimalism at the settlement layer

Coinbase's x402 embeds payment into HTTP itself: the server returns a 402 with a quote, the agent signs a USDC transfer into a request header, and the retried request settles. No accounts, no API keys, no minimums. Its bet: the machine economy needs a permissionless, lowest-friction native rail — and stablecoins are the only medium that qualifies.

AP2: a coalition play at the trust layer

Google's Agent Payments Protocol doesn't settle anything. It handles authorization and accountability: users issue verifiable mandates to agents; merchants and payment providers verify that a given transaction was genuinely authorized. Sixty-plus institutions signed on, card networks included. Its bet: the bottleneck isn't how agents pay — it's who answers when things go wrong.

Agent Pay / Intelligent Commerce: incumbent defense at the distribution layer

Visa and Mastercard extend their existing tokenization stack to agents: controlled delegated credentials running over the existing merchant network. Their bet: distribution is the moat — a hundred million merchants already accept cards, and nobody re-plumbs acquiring for agents.

Our read

Coexistence by layer is likelier than a winner-take-all: cards keep existing e-commerce, x402-style rails take net-new machine-to-machine volume, and AP2-style mandates become the authorization middleware both sides need. Watch three metrics only: merchant integrations, default choices inside agent frameworks, and how regulators classify unattended transactions. Whoever sets de facto standards on those three becomes the next TCP/IP.