Keyrock Report: 76% of AI Agent Transactions Fall Below Visa’s $0.30 Fee Floor

Keyrock ‘Who Pays the Agent’ Analysis: USDC Dominates 98.6% of AI Agent Payments

The report, co-published with Coinbase, Tempo, and Virtuals, documents however machine-to-machine payments moved from a theoretical conception to a functioning ecosystem successful 1 year. Agents present wage for API access, information queries, and compute resources successful existent time, with nary quality successful the loop. The mean transaction size has stabilized adjacent $0.48.

Coinbase built x402, a protocol that repurposes the long-dormant HTTP 402 presumption codification to alteration stablecoin payments betwixt machines. Stripe and Tempo co-authored the Machine Payments Protocol, known arsenic MPP, a payment-method-agnostic modular that handles stablecoins, recognition cards, and Lightning Network payments done a azygous HTTP flow. Google released AP2, an authorization furniture that allows users to delegate spending authorization to agents utilizing cryptographic mandates. Visa extended its existing paper rails to proviso AI-ready tokenized credentials agents tin contiguous astatine checkout.

Image source: Keyrock study “Who Pays the Agent? The Race for Frictionless Machine Payments.”

Keyrock’s investigation shows these 4 protocols are not purely competing. They are assembling into a layered stack. AP2 handles authorization. x402 and MPP grip colony beneath it. The question the study focuses connected is which companies seizure the astir layers, and truthful pull the astir value.

According to the report, Coinbase and Stripe each span 5 of six stack layers. Coinbase controls colony done Base, wallets done its AgentKit platform, the outgo protocol done x402, and governance arsenic a spouse successful AP2. Stripe mirrors this done Tempo for settlement, Privy for wallets, Bridge for routing, and MPP for the protocol layer. Circle covers 4 layers. Google and Visa presently span 2 and one, respectively.

The economics marque crypto rails adjacent to mandatory for this market. Keyrock’s information shows that 76 percent of cause transactions autumn beneath the $0.30 fixed-fee level charged by paper networks. A USDC transportation connected Base costs astir $0.0001, which is astir 0.03 percent of a $0.31 payment. On Stripe, that aforesaid outgo would outgo $0.309 successful fees, leaving the merchant with $0.001.

One of the astir concentrated findings successful the study is stablecoin dominance. Of the 176 cardinal payments recorded, 98.6 percent settled successful USDC. Keyrock flags this arsenic a systemic hazard that fewer successful the manufacture are publically addressing. If Circle faces a regulatory challenge, a de-peg event, oregon a method outage, the cause payments ecosystem has nary fallback.

Incumbents moved to unafraid positions crossed the stack done acquisitions. Capital One acquired Brex for $5.15 billion. Mastercard purchased BVNK for $1.8 billion. Stripe acquired Bridge for $1.1 billion. Together, these and related deals correspond much than $8 cardinal deployed successful 12 months.

Keyrock notes that machines already predominate onchain activity. On Gnosis Chain, AI agents via the Olas web relationship for implicit 75 percent of Safe transactions connected highest days. On Base and Optimism, bots and automated contracts devour much than 50 percent of gas. The existent enactment is mostly extractive, including arbitrage and volume farming. The displacement to productive cause commerce, wherever agents wage for services that make worth for extremity users, is what the caller infrastructure is designed to enable.

The study besides points to the nonaccomplishment of OpenAI‘s ChatGPT Instant Checkout, which was shelved successful March 2026 aft lone astir 30 Shopify merchants actively utilized it. The merchandise lacked income taxation collection, fraud prevention, and multi-item cart support. Keyrock interprets the result arsenic confirmation that agents transacting done protocol endpoints, not ocular checkout flows, is the viable model.

Regulatory uncertainty is the binding constraint identified crossed each sections. Three large frameworks scope enforcement wrong weeks of each other: MiCA’s transitional play ends July 1, 2026, the GENIUS Act’s implementation deadline falls July 18, and the EU AI Act’s high-risk obligations instrumentality effect August 2. None incorporate provisions for autonomous machine-to-machine transactions.

Liability is unresolved. With recognition cards, merchants carnivore chargeback hazard and consumers person protection. With stablecoins, erstwhile funds onshore successful a merchant wallet they cannot beryllium recalled. As x402 creator Erik Reppel of Coinbase told Keyrock, the hazard moves wholly to the consumer. American Express moved archetypal to code this commercially, launching Agent Purchase Protection connected April 14, 2026, covering erroneous purchases made by verified agents wrong its registered ecosystem.

The study concludes that the instrumentality system already exists. It is not yet doing meaningful commerce. The infrastructure is ready. The regulatory clarity is not.