Who pays / Fintech & paymentsEditorial brief · 16 October 2026

Your AI agent bought the wrong thing. Guess who gets the box.

Checkout has moved into the chatbot. American Express’s new safety net for agent mistakes comes with one small instruction: try the merchant’s returns desk first.

The finding

American Express promises to protect you from eligible mistakes your AI agent makes. Step one of that protection: start a return with the merchant, “where possible.” The industry first, it turns out, comes second. [C7]

Our reading: the merchant’s returns desk is the first stop for the robot’s error. Who finally eats the cost? Nobody has published that, and we are not going to make it up.

Hands filling a cardboard shipping box with protective wood wool.
Packing a physical order. Photo: Meanwell Packaging / Wikimedia Commons, CC BY 2.0. Illustrative context, not an agent-order record.
Delegated buying≪1%

Checkouts an agent completes on its own, in Accertify’s data. They had to reach for basis points.

Through Sep 2026 · Accertify [C10]
Discovery+62%

AI-referred retail traffic, year over year. Chatbots are very good at pointing.

Jul 2026 · Adobe via DC360 [C32]
Conversion+60%

Conversion rate of AI-referred visits relative to non-AI visits. The pointing works.

Jul 2026 · Adobe via DC360 [C32]

The two Adobe figures cover United States retail sites. A referral is a chatbot saying “try this shop,” not a chatbot buying anything.

01 / Define the market

How much shopping have we actually handed to the robots?

“Agentic commerce” covers two very different things: an AI suggesting a product, and an AI actually paying for it. This brief is about the second, the one that can go wrong on your card. Accertify’s consortium puts autonomous checkout well below 1% of transactions. That is a window into its members’ traffic, not a census of the planet. [C10]

Chart 1 / The shape

AI referrals grew in every window. The growth rate is coming back down to Earth.

United States retail · year-over-year traffic growth (%) · discrete Adobe snapshots

Read as snapshots, not a trend line. Adobe’s windows are holidays, single days, months and quarters, and some overlap. These bars show reported growth in visits, not a continuous monthly trend and not the number of purchases an agent made.

Sources: Adobe 2024 windows [C26] · Jul 2025 [C28] · holiday 2025 [C29] · Q1 / Mar 2026 [C30]; via Digital Commerce 360 May [C31] and Jul 2026 [C32]. Data through Jul 2026.

More visits from a chatbot tell us nothing about how many purchases the chatbot completed. Pointing is not paying.

02 / The exposure base

How big is the robots’ share of the till?

In an earlier sample, Accertify counted 7,741 agentic transactions out of 3.878 billion: roughly two per million. You will struggle to find them in the chart below; so did we. Its later autonomous-checkout account uses a different definition, so no, you cannot divide one by the other and call it a growth rate. [C11]

Chart 2 / The split

The agentic slice is so thin it needs an arrow

Accertify consortium · 1 Dec 2025–15 Mar 2026 · share of transactions (%)

0.0002% agentic
7,741 transactions

0%99.9998% remaining100%
2 / 1m

About two agentic transactions per million in this historical sample. The other 999,998 were not counted as agentic, which is not the same as untouched by AI.

The orange pointer locates a slice too small to see; its line width is not the share. “Remaining” does not mean no AI was involved. Counts and denominator come from supplied verified research; the denominator is rounded.

Source: Accertify, 26 Mar 2026 [C11]. Share calculated as 7,741 ÷ 3,878,000,000. This is not an estimate of total industry volume.

03 / Follow the return

Who meets the mistake before the safety net does?

Amex calls its planned backing an industry first. Read the conditions and the order of events is the interesting part: an eligible agent error goes through a merchant return attempt before this extra protection applies. The merchant gets the mistake first; the industry first arrives later. [C7]

01 / THE SHOPPER

Your agent gets it wrong

The planned protection covers eligible charges made by agents registered with Amex and integrated with its Agentic Commerce Experiences developer kit. The bot your cousin built over a weekend, unregistered, is not on the list.

02 / THE MERCHANT

Someone starts a return

Before anything else, the shopper has to start a return with the merchant, where possible. Congratulations to the returns desk, the new front line of artificial intelligence.

03 / AMERICAN EXPRESS

Protection, conditionally

Claims are subject to eligibility and review. Full terms are “forthcoming.” Ordinary card disputes remain available, as they were before anyone said “agentic.”

Process, not a monetary waterfall. Source: Amex Agent Purchase Protection [C7a–e], as of 16 Oct 2026.

What this does not prove: that the merchant eats every refund, the full purchase price or the final loss. Nobody has measured who ends up paying, and we are not going to guess.
04 / Why now

What changed this week? Mostly, who gets to press “buy.”

13 OCT 2026

Shopify opens Shop MCP checkout. The agent completes the purchase once the shopper confirms, and the order lands in the merchant’s admin looking like any other order. The robot does not get a special badge. Shopify [C1]

13 OCT 2026

Amex publishes Intent Intelligence. A record of what you authorised the agent to do, for fraud checks, authorisation and disputes. Receipts for your intentions, essentially. American Express [C5]

09 OCT 2026

Accertify sizes the gap. Its new account separates the big pile of “AI shopping activity” from autonomous checkout, which it measures in basis points. Accertify [C10]

Latest developments in the supplied evidence, within the 18 July–16 October 2026 research window.

05 / Who pays

We know who answers the door. We don’t know who pays the bill.

Interpretation · 112 words

On 13 October, checkout moved into the agent and your intent moved into the payment record. Very modern. Neither, on its own, moves the cost of an agent’s mistake anywhere. Shopify’s agent orders still arrive as ordinary orders. Amex’s planned protection asks for a merchant return attempt first, where possible. So when the robot buys the wrong thing, the returns process hears about it first. That is not the same as the merchant losing the money: nobody has published who reimburses whom afterwards. The good news is that the volume is tiny. The bad news is that tiny is exactly when the conditions get written, and nobody reads conditions until they matter.

06 / The stress point

Are chatbot shoppers at least buying?

Adobe’s AI-referred visits went from converting worse than everyone else to converting better. By July 2026, their conversion rate was reported as 60% higher than non-AI visits. Lovely news for the channel. It says precisely nothing about what happens when an agent gets the order wrong. [C32]

Chart 3 / The change

AI referrals went from window-shopping to out-converting everyone else in 16 months

United States retail · conversion rate relative to non-AI visits (%)

Zero means equal conversion rates. +60% means 1.6 times the non-AI rate, not 60 percentage points more conversion. These are reported snapshots, not proof that AI caused the improvement or completed the purchase.

Sources: Adobe Mar 2025 / Mar 2026 [C30] · Jul 2025 [C28]; via Digital Commerce 360 May 2026 [C31] · Jul 2026 [C32]. Five observations; no values interpolated.

07 / Risks & counter-case

Fine, but what if we’re overreacting?

The exposure is still small.

Accertify’s measured autonomous-checkout share makes it hard to argue for a big burden today. These data do not show a merchant-loss crisis: basis points of anything are not a crisis yet. A consortium is not the whole market, either. [C10]

A return is not a final loss.

Starting a return tells you nothing about how it ends or what it costs. Amex’s conditional protection and plain old card disputes may still do the heavy lifting. Nobody has published an agent-error loss rate or a reimbursement split, and we looked. [C7]

08 / Watch list

What would change our minds?

Editorial checkpoints, not scheduled company announcements.

31 OCT 2026 / TERMS CHECK

Read the small print, once it exists.

Recheck whether Amex has published final coverage conditions: who gets reimbursed, what the return attempt has to involve, and which costs are covered. “Forthcoming” is not a term.

31 DEC 2026 / VOLUME CHECK

Ask for a count. And a denominator. Please.

Look for holiday disclosures of agent-completed transactions with consistent definitions. What would actually change the answer: a measured return or chargeback rate, next to realised losses.

Evidence / Method

Sources and claims log

31 scoped claims: 27 verified, 1 contested, 3 unverified. The 27 include an explicitly labelled interpretation and a derived calculation. The contested and unverified claims are excluded from the story and reel. “Verified” follows the supplied research protocol; it does not mean independently audited company data.

  1. Shopify, Shop MCP changelog, 13 Oct 2026. C1a–b.
  2. American Express, Intent Intelligence (13 Oct) and Agent Purchase Protection conditions. C5, C7a–e.
  3. Accertify, October consortium account and March reality check. C10a–c, C11, D1.
  4. Adobe, 2024 referral windows, July 2025, holiday 2025 and Q1 2026. T1–T6, V1–V3.
  5. Adobe data via Digital Commerce 360, May 2026 and July 2026; corroborating secondary reports in MarketingTech and Elogic. T7–T8, V4–V5.
What was verified, derived or left out?
Claim IDsEvidence and publication decision
C1, C5, C7, C10Primary company material. Current October developments and return-first language rechecked. Protection is a future commitment, not universal live coverage.
C11, D1Historical counts retained from supplied verified research. Reopened source text states approximately one in 500,000; the exact counts were not freshly recovered. Derived share: 0.0001996%.
T1–T8Eight Adobe-origin growth snapshots with unequal, overlapping periods. Six directly primary-sourced; two via trade reports. Not a comparable monthly series.
V1–V5Five relative conversion gaps. Last two via secondary reports relaying Adobe. Observational, not causal.
I1Editorial interpretation: merchant return handling precedes conditional protection. Final loss allocation is not established.
G1–G4Excluded: seller-of-record assertion, reported absence of disputes, an unverified rule-change date, and unresolved cumulative Adobe figures.
Why not chart tokens, assistant users or a monthly transaction trend?

The supplied research contains no eight comparable primary observations for those series. Token counts and transaction shares have different denominators. General assistant users are not shopping users. Accertify’s March and October definitions differ. The first exhibit therefore presents eight labelled referral snapshots instead of inventing a continuous trend. No monetary liability split or agent-error return rate was found.

Photography and reuse credits

The photograph provides material context, not evidence of an agent purchase or return. Commons metadata confirmed permitted licences. The original is linked directly because asset-hosting credentials were unavailable. Social image is a 1200 × 630 crop of the first photograph.