PegasusBlock, allowlist, or open the door. The merchant’s agent decision.
Reggie Britt · October 2026
The customer
The customer at the door is now software.
The next visitor to your store may not be a person, and every merchant now has to decide whether to let it in. Meta’s Muse and OpenAI’s Dots are already helping millions of people choose products, bid in auctions, book travel and order groceries, The Wall Street Journal reported this month.
For consumers, that is relief. For twenty years, technology pushed work onto the customer: book your own flight, troubleshoot your own device, be your own bank teller. Agents promise to take that work back.
For the merchant in the middle, the work does not disappear. It moves to you. The playbook built for search engines and social feeds does not say what to do when the visitor is an agent acting for someone else.
Four doors
The biggest retailers picked differently.
Three of the answers sit on one line, from keeping control to chasing reach. The fourth is a different move entirely.
Building your own agent trades the outside agent’s reach for something only the merchant has. DoorDash CEO Tony Xu’s argument is that only his company knows what is in stock and can run the pickup and delivery. Customers may trust an outside agent’s recommendation more, but an in-house agent sees the real inventory and promotions, and can fix the order when it goes wrong.
The question moved
Not who the buyer is. What the agent was allowed to do.
Federal Reserve Governor Christopher Waller made the point at Sibos 2026 in Miami on September 29: the task shifts to proving “that an agent has the authority to pay on the buyer’s behalf.”
Waller split agentic commerce into two models. In the agent-assisted model, the agent finds the product and the buyer stays in control. In the agent-delegated model, the buyer grants authority and the agent shops and pays within guardrails. The second is where a merchant’s exposure lives.
Most merchant controls answer two questions: is this person signed in, and can this card pay. Neither says what the agent was permitted to buy, or who answers for it when it gets it wrong. Card networks are publishing specifications to register agents and record approvals, but who defines the authority that travels with a payment is still open.
KYC asks who the customer is. KYA asks what the agent may bind you to.
The price of each door
Every door has a price, and most merchants can’t pay Amazon’s.
Blocking costs reach
Amazon can afford it: Prime members keep shopping there whether or not their agent gets in, and a Rosenblatt Securities analyst argues Amazon owns too much of the chain to share any of it. Most merchants own one link. Block the agent and it simply recommends someone else.
An allowlist costs scale
Each approved agent is its own deal. That works for Target. It does not work for a mid-market merchant facing dozens of agents, each with its own rules.
Opening costs control
The Journal lists weaker market power, a more distant customer, and agent mistakes that come back as returns and chargebacks. Each of those is a liability question: when an agent buys the wrong thing, who pays?
Being found isn’t one problem
BrightEdge CEO Jim Yu notes that different AI models weigh purchases differently, so there is no single ranking to optimize for.
The door you choose matters less than whether you can tell who is walking through it.
The honest numbers
Slope, not level.
Agent buying is small today and growing fast, and both halves matter.
Both figures are BrightEdge estimates drawn from its own client base, as reported by The Wall Street Journal. They are one vendor’s view, not a market-wide count.
The honest reading is that the level is low and the slope is steep. That cuts against both easy answers. There is no reason to panic over today’s volume, and no reason to wait for it to arrive before building the door.
What to build
Build the decision points now. Pick the vendor later.
Whatever door you choose today, build it so you can change doors without rebuilding. That means four decision points in your transaction path.
Who is the agent?A place to check an agent’s identity before it can act, not just a bot score at the edge.
Who authorized it?A record that a real, accountable person or business stands behind the request.
What is it allowed to do?Spend, frequency and counterparty limits enforced at the gate.
How far does that authority travel?A rule for when an agent acts for another agent, or when authority is unclear: step up, refer to a person, or decline.
The first three are converging: authorization standards are consolidating inside the FIDO Alliance, and card networks are building agent registries. The fourth is still open. No deployed protocol yet proves which human authorized which agent several hops down the chain.
That is why the advice is to build readiness now and commit to a vendor later. KYA is a settled category, not yet a settled standard. Decide, too, who absorbs returns and chargebacks from agent errors, before your first dispute decides it for you.
The one question
Ask it this quarter.
When an agent transacts with you, can you tell whether an accountable party stands behind it, and can you prove one stands behind you?
The first half is defense: letting good agents in without waving bad ones through. The second half is market access. As networks and platforms start admitting only agents they can verify, a business that cannot present its own verifiable identity gets filtered out.
Selling online? Pegasus Commerce puts these decision points in front of a store you own →
Run on IBM i? Pegasus4i delivers it on the platform you already own ↗
Sources
- Asa Fitch, “AI Agents Bring New Headaches to Online Sellers”, The Wall Street Journal, October 2026. Source of the Muse and Dots, Amazon, Target, Walmart, DoorDash, BrightEdge and Rosenblatt details.
- Christopher J. Waller, “Payments in the Age of AI Agents”, speech at Sibos 2026, Miami, September 29, 2026.
- PYMNTS, “Fed’s Waller Says AI Shopping Changes What Banks Need to Authenticate”.
Map your own decision points.
Open a free workspace, set an agent’s rules, and see which carts your store would refuse. No sales call required.