Agentic payments, explained: the five protocols and what each one does

What makes a payment agentic

An automated payment repeats a decision a human already made. A subscription renewal, a payroll run, a nightly sweep into a treasury account: the amount, the counterparty and the timing were fixed in advance. The software executes. It does not choose.

An agentic payment hands the choice to software. The agent selects what to buy, from whom, at what price, at the moment the need appears. A human or a business sets the envelope it operates inside: a budget, an allowlist of merchants, a ceiling per transaction, an expiry.

That is the distinction, and it is a permission question rather than a technology question. Which is why most of the unsolved work in this category sits at the authorisation layer, not the settlement layer. Moving value is a solved problem in several different ways. Deciding what an unattended process may spend, and proving afterwards that it stayed inside the lines, is not.

Why card rails do not fit inside one web request

Card networks were designed around a human at a checkout. A merchant account, an issuer, an acquirer, a cardholder, a dispute window measured in weeks and a fee floor that assumes a basket of at least a few dollars. Every one of those assumptions strains when the buyer is a process paying a fraction of a cent for a single API call.

There is also a timing problem. A card authorisation is a separate round trip through several institutions. An agent fetching a page or calling a tool is mid-request and needs a decision inside that request.

x402 turns the HTTP 402 status code into the payment instruction. Per the protocol repository, the response carries PaymentRequirements, the payer returns a PaymentPayload, and a facilitator verifies and settles. The x402 protocol documentation states that the protocol charges no fee of its own, so payers cover network fees only, and that it is blockchain-agnostic across EVM chains and Solana.

How often does a 402 actually go out? Cloudflare's chief strategy officer said at Consensus in May 2026 that the network sends over a billion HTTP 402 responses a day, as quoted by CoinDesk. Treat that as a remark from a conference stage, not a published Cloudflare statistic.

Nobody can tell you how much of this is real commerce

According to TRM Labs, roughly $52.7M settled across 198.9 million x402 settlements on Base, Solana and Polygon since May 2025. Screen out the obvious wash and self-dealing and $25.62M looks like plausible commerce. Between 0.6% and 7.5% of that screened total appears agentic, which TRM states as roughly $5,000 to $11,000 a month. $52.47M of $52.68M, or 99.6% of value, settled in USDC.

Other measurements point elsewhere because they count different things. Chainalysis counts well over 100 million cumulative x402 transactions on Base through Q1 2026, and reports that payments of $1 or more rose from 49% of value in early 2025 to 95% by early 2026. CoinDesk cites Artemis data putting real daily x402 volume around $28,000, with an average payment around $0.20 against roughly 131,000 daily transactions. BlockEden.xyz recorded daily x402 transactions falling from about 731,000 in December 2025 to about 57,000 in February 2026, a decline of over 92%.

Coinbase's own cumulative figure in late April 2026 was roughly 165 million transactions, about $50 million of volume and 69,000 active agents, published the week Agent.market launched.

Different counting rules, different windows, different answers. If you want the detail on how those numbers get collected and compared, how the corpus was measured lays it out.

A lot of transactions are happening. A small share of the value looks like an agent buying something.

The five protocols, on the layer each one owns

x402 is the payment layer, and the only one with meaningful volume. Its governance moved in 2026. The Linux Foundation announced the x402 Foundation on 2 April 2026 at the MCP Dev Summit North America in New York, with Coinbase contributing the protocol. The operational launch followed on 14 July 2026 with 40 member organisations, including 17 premier members such as Adyen, AWS, American Express, Circle, Cloudflare, Coinbase, Google, Mastercard, Shopify, Stripe and Visa.

AP2 owns authorisation. The specification sets out a mandate model: what an agent is permitted to buy, expressed as credentials another party can check. Cite it for authorisation design, not for anything about x402's behaviour.

MPP, from Stripe and Tempo, launched on 18 March 2026 per Stripe's announcement. It covers subscriptions, streaming usage, cancellation and reconciliation. A single 402 exchange does none of those.

Pay Per Crawl lets publishers price crawler access with Cloudflare as merchant of record, using HTTP 402, and is in private beta. AI Crawl Control lets publishers see and sort AI crawlers by purpose. This is the access layer, and the demand case may be strongest here. Cloudflare measured crawl-to-referral ratios for the week of 19 to 26 June 2025 of nearly 71,000 to 1 for Anthropic, 1,600 to 1 for OpenAI, 202.4 to 1 for Perplexity, 40 to 1 for Microsoft and 9.4 to 1 for Google. Those are 2025 figures, and Cloudflare notes they have improved by more than an order of magnitude since.

Monetization Gateway is the delivery layer. Published on 1 July 2026, it lets Cloudflare customers charge for any protected asset, whether a page, a dataset, an API or an MCP tool, settling in stablecoins over x402. There is a longer write-up in Cloudflare's Monetization Gateway: pricing the web for agents.

Cloudflare sits in front of 25.8% of all websites, according to the September 2026 W3Techs survey. Any settlement default it picks becomes the default for a quarter of the web.

What a buyer should do while this is unsettled

Do not standardise on a rail yet. Separate the pieces, because the layers are moving independently.

• Keep authorisation and settlement apart. Mandates and payment instructions are different objects from different vendors. Fusing them means redoing the integration when either one changes.
• Budget at the envelope, not the transaction. If your unit economics depend on an average payment near $0.20, card fees are the entire problem, and onchain settlement stops being optional.
• Plan for reconciliation. MPP explicitly covers cancellation and reconciliation. One-shot 402 payments do not. High-frequency, low-value calls need both.
• Ask vendors for screened volume. The distance between 198.9 million settlements and $25.62M of plausible commerce is the story. Cumulative counts are marketing. Screened counts are diligence.
• Read the governance, not the landing page. A published spec and an operating foundation are worth more than a partnership logo. Vendor copy in this category is promotional, and answer engines repeat it back at you; AEO compared with SEO explains why that shapes what you find when you research.

If you want the checklist version of the same work, the free playbook is the place to start.

Nobody can tell you which of these five wins. The layers, at least, are settling into shape.