08 — Merchants, Retailers & Marketplaces in the Agentic Channel

Cross-references: see 01 — Introduction & Taxonomy for definitions (Human-Present vs Human-Not-Present, Merchant-of-Record), 03 — AP2 and 04 — ACP for the protocols referenced below, 06 — Card Networks for Trusted Agent Protocol and Agent Pay, and 10 — Regulation & Compliance for the chargeback and dispute frameworks that the merchant commitments in this section inherit.

A common misconception in mid-2025 was that agentic payments were, fundamentally, a payments story — a rearrangement of how card rails, wallets and tokens authorise money movement. By mid-2026 it is clearer that the decisive battleground is the merchant surface: who controls the product feed, who owns the shopper relationship, who remains Merchant-of-Record (MoR), and who pays for the traffic that used to arrive via Google Search and Meta ads. This section surveys how retailers, marketplaces, aggregators and travel OTAs have responded between September 2025 (the first ACP-powered Instant Checkouts in ChatGPT) and April 2026 (the first full quarter of the Google/Shopify Universal Commerce Protocol, UCP, in public use).

1. The merchant's strategic calculus: opportunity and threat

For most large direct-to-consumer retailers the agentic channel presents a genuinely asymmetric decision. On the opportunity side:

• A new demand surface. ChatGPT reports more than 700 million weekly users in autumn 2025, a comparable scale to Google's shopping surface; Perplexity, Gemini, Microsoft Copilot and Claude collectively add another several hundred million.[^1][^2] Any merchant that is invisible on these surfaces is effectively invisible to a growing share of discovery intent.
• Higher-intent traffic. Early public claims from Etsy and Shopify suggested that agentic sessions skew towards decided, high-intent buyers, not browsers — because conversational context compresses the discovery funnel.[^3]
• Reduced cart abandonment. Because ACP and UCP-style flows settle payment inside the agent surface using tokenised credentials that the user has pre-vaulted (Stripe Link, Shop Pay, PayPal, wallet passkeys), the classical "checkout form abandonment" step largely disappears.[^4]
• Merchant-of-Record preservation. Critically, both ACP and UCP are designed so that the retailer remains MoR: fulfilment, tax, returns, loyalty and customer-service liabilities sit with the merchant, not with OpenAI or Google.[^5][^6] This is a deliberate design choice to get retailers to adopt, and it is also the axis on which the retailer retains some economic leverage.

On the threat side:

• Disintermediation of the brand. When a shopper says "order me dish soap," the agent, not the retailer, chooses between Dawn, Seventh Generation and a private-label SKU. The retailer's merchandising, upsell, bundle and "you might also like" logic is displaced by the agent's ranker.
• Loss of first-party data. In most current deployments the agent sees the full conversation history and the shopper's stated preferences, while the retailer sees only a cart and a shared payment token. Retargeting, email capture, loyalty enrolment and cohort analytics all degrade.
• Brand commoditisation. A product becomes a row in an agent's JSON feed. Photography, page design, brand voice and creative differentiation — the investments retailers have made in their owned DTC sites — are stripped away in favour of structured attributes.
• Terms-of-use collisions. As Amazon's dispute with Perplexity demonstrates (discussed in §6), some retailers view undisclosed agent traffic as unauthorised access even when the underlying shopper is authenticated.[^7]
• Margin compression from platform fees. OpenAI takes a small transaction fee on ACP orders routed through ChatGPT;[^8] Google's UCP position on fees remains less transparent at time of writing but follows a similar "small per-transaction" pattern for agentic checkouts in AI Mode.[^6]

The net position for most retailers has been to adopt defensively: the cost of being absent from ChatGPT, Gemini or Copilot is judged higher than the margin foregone to platform fees and the data foregone to the model vendor. The interesting secondary question — which we return to in §10 — is whether that calculus holds once agentic traffic reaches double-digit shares of revenue.

2. Instant Checkout launches on ACP: Etsy, Shopify, Walmart

OpenAI and Stripe jointly announced the Agentic Commerce Protocol (ACP) and the first Instant Checkout in ChatGPT on 29 September 2025, with Etsy as the launch merchant and Shopify's seller base queued to follow.[^9][^4] The sales-impact signal was immediate and loud: Etsy's stock jumped roughly 16% intraday on the announcement, reflecting market expectations about access to ChatGPT's weekly active users.[^3]

The launched (production) footprint as of April 2026:

• Etsy — 29 September 2025. Single-item purchase flow at launch; over 2 million U.S. Etsy sellers enabled programmatically via Etsy's payments platform.[^4][^9] Etsy retains MoR status; a shared payment token carries the delegated authority from the shopper's vaulted card.
• Shopify sellers — phased from 29 September 2025 onward. OpenAI and Shopify described an opt-in rollout to "millions" of Shopify merchants, leveraging Shop Pay as the underlying wallet; multi-item carts and subscriptions were explicitly on the roadmap.[^4][^9]
• Walmart and Sam's Club — announced 14 October 2025. The press release frames Instant Checkout in ChatGPT as the "first step" of a multi-year OpenAI partnership covering Sparky (Walmart's own assistant), enterprise ChatGPT and OpenAI Certifications for associates.[^10][^11][^12] Walmart's FY2025 revenue base of roughly $681 billion makes it the most material ACP merchant to date by GMV potential.[^10]

Publicly verifiable sales-impact data as of the cut-off is thin. OpenAI has not released aggregate ACP GMV; Etsy has referenced "meaningful" incremental orders in analyst calls but has not broken out ACP volume; Walmart's own ACP volumes have not been disclosed. Shopify's Q4 2025 and Q1 2026 commentary references agentic checkout as a contributor to buyer-count growth rather than a headline line item. In other words, the channel exists, it is measurable, but public figures should be treated as directional.

Status taxonomy to use when reading merchant announcements in this space:

Label	Meaning
Launched	End-to-end purchase is live in production for end-users, in at least one market.
Piloted	Gated to a user subset (e.g., ChatGPT Plus, one region, one SKU class).
Announced	Press-released intent; no production traffic yet.
Speculative / press-implied	Referenced by analyst or third-party reporting but not confirmed by the party itself.

3. UCP: what Google + Shopify standardise that ACP does not

Announced at NRF's Big Show in January 2026 and published on 11 January 2026 in the Google Developers Blog, the Universal Commerce Protocol (UCP) is positioned by Google as an open-source, AP2-compatible abstraction layer that covers "the full commerce journey — from discovery and consideration to purchase and order management."[^6] The launch partner set is substantially broader than ACP's: Shopify, Etsy, Wayfair, Target and Walmart as core collaborators, plus more than 20 endorsing partners including Adyen, American Express, Best Buy, Flipkart, Macy's, Mastercard, Stripe, The Home Depot, Visa and Zalando.[^6]

UCP and ACP overlap but differ in scope and philosophy:

Dimension	ACP (OpenAI + Stripe)	UCP (Google + Shopify + partners)
Primary author	OpenAI + Stripe	Google Commerce (Amit Handa, Ashish Gupta)[^6]
Scope	Checkout + payment delegation	Full lifecycle: discovery, consideration, purchase, post-order
Transport	REST over HTTPS with a delegated SharedPaymentToken	HTTP + MCP + A2A bindings (pluggable)[^6]
Payment layer	Stripe-mediated shared token; merchant remains MoR	Open payment handler interface; AP2 mandates provide cryptographic consent (see 03)[^6]
Catalog / inventory	Minimal product schema; relies on merchant APIs	Standardised capability schema covering real-time inventory, dynamic pricing, member benefits, variants[^6]
Consumer surfaces	ChatGPT today; other ACP hosts in future	Google AI Mode in Search, Gemini app, and others pluggable[^6]
Merchant-of-Record	Merchant	Merchant (explicit) — "embedded option" allows fully custom checkout UI[^6]
Governance	Open-source but centrally curated by OpenAI + Stripe	Open-source, community governance flagged as a goal[^6]
Status (Apr 2026)	Launched with Etsy, Walmart, Shopify sellers	Launched in staged rollout across AI Mode; production flows with Shopify, Etsy, Wayfair, Target[^6]

The practical answer to the question "ACP or UCP?" in 2026 is both. Walmart and Etsy appear on both launch rosters; Shopify is a co-author of UCP and a primary participant in ACP. This is characteristic of the way payments standards diffuse: merchants will add whichever on-ramp each large consumer surface mandates, and convergence (if any) will occur in the payment layer via AP2 mandates and Visa's Trusted Agent Protocol rather than in the merchant schema. (See 06 — Card Networks.)

4. Product feeds and agent-readable catalog standards

A less glamorous but increasingly material story sits under both ACP and UCP: the feed. Agents need structured, authoritative, low-latency product data in a machine-first format. Three threads are converging here.

schema.org/Product extensions. UCP explicitly standardises a "capability schema" that goes beyond the legacy schema.org/Product + Offer markup used by Google Merchant Center. The UCP schema adds first-class fields for real-time inventory, dynamic pricing, member-pricing overlays, variant relationships and return policies.[^6] This reflects a long-running complaint from agent builders that classic product JSON-LD is too static — price and availability drift within hours and shoppers (or their agents) end up in "product not available" failure modes at the cart step.

Google Merchant Center as an agent catalog. In parallel, Google has repositioned Merchant Center feeds as an agent source: retailers who already ship accurate, fresh feeds for Shopping ads get UCP surface eligibility effectively for free. Guidance from January 2026 emphasises GTIN/MPN hygiene, sub-hourly stock refreshes and variant completeness as gating criteria for AI Mode inclusion.[^6]

Mirakl Nexus and marketplace aggregation. Mirakl, which powers the marketplace tier for Best Buy, Lowe's, Macy's, Carrefour, John Lewis and Ulta Beauty among others, announced Mirakl Nexus, a so-called "Agentic Commerce Brain," at its Mirakl Summit in spring 2025. Mirakl reported FY2025 ARR of $218 million (+23$15 billion.[^13][^14] Nexus' pitch to retailers is that it normalises third-party seller catalogs into an agent-consumable feed with a uniform returns and post-sale API — in effect, a shared UCP-ready surface for the long tail of marketplace SKUs.[^13][^15]

Live inventory as the hardest problem. An agent that books a cart at 14:03:12 and submits payment at 14:03:19 must not encounter a mid-flight stockout. Both ACP and UCP therefore push toward reservation semantics (hold the cart for N seconds, finalise on payment) rather than the legacy "optimistic add-to-cart" model. This is straightforward for Shopify, Shop Pay and Stripe's merchant integrations, but still operationally difficult for the long tail of headless-commerce and custom ERP retailers, where real-time inventory is actually a batch job in a trench coat.

5. AI-native retailers and search frontends

The surfaces that are the new storefront:

• ChatGPT Shop / Instant Checkout. OpenAI's consumer surface; ACP host; Etsy, Shopify sellers and Walmart live as of Oct 2025; Instacart as of Dec 2025; Booking, Expedia and Tripadvisor via the ChatGPT Apps SDK (Oct 2025).[^4][^16][^17] Status: launched.
• Perplexity Comet + "Buy with Pro." Perplexity launched "Buy with Pro" for Perplexity Pro users ahead of Thanksgiving 2024, then expanded to all U.S. users in November 2025 with a PayPal-powered "Instant Buy" rollout covering over 5,000 PayPal-integrated merchants including Abercrombie & Fitch, Ashley Furniture, Fabletics, Adorama and Newegg.[^18][^19] Comet, Perplexity's agentic browser, executes the actual purchases by driving merchant sites. Status: launched (but with the Amazon carve-out discussed in §6).
• Microsoft Copilot Shopping & Bing. Microsoft signed on as a launch partner of Mastercard Agent Pay in April 2025 and integrates agentic-commerce primitives via Azure OpenAI, Copilot Studio and Microsoft Shopping.[^20][^21] Microsoft is also a named partner in Visa's Trusted Agent Protocol (October 2025).[^22] Agentic purchase completion inside Copilot has been demonstrated publicly but, unlike ChatGPT or AI Mode, has been less aggressive about pushing production merchants into a single Instant-Checkout surface. Status: piloted / partially launched, depending on vertical.
• Google AI Mode and Gemini app. With UCP in production from January 2026, AI Mode in Search and Gemini both host agentic checkouts against UCP-compliant merchants.[^6] Status: launched, scaling.
• Claude (Anthropic). Claude underpins the MCP spec and is widely used for agentic workflows, but as of the cut-off Anthropic has not launched a consumer Instant-Checkout surface comparable to ChatGPT's. Status: not launched at the consumer-checkout layer; very much launched at the developer-agent layer.

6. The Amazon question

Amazon is conspicuously absent from ACP, UCP, Trusted Agent Protocol, Mastercard Agent Pay and AP2's merchant rosters. That absence is a deliberate strategic posture, not an oversight.

Amazon's own agent, Rufus, is built inside Amazon's walled garden: it helps shoppers discover, compare and summarise reviews, but outbound agent orchestration against third-party Instant-Checkout surfaces is not currently supported. Amazon is also building product-detail-page agent experiences and agentic Alexa+ flows internally. The business reason is straightforward: Amazon's margins depend on retail media (advertising revenue reported at $56 billion run-rate in 2024) and on private-label merchandising, both of which are disintermediated by any external agent that ranks products for its own reasons.

The Amazon × Perplexity dispute is the first major legal flashpoint. In late October / early November 2025, Amazon sent Perplexity a cease-and-desist letter demanding Comet stop transacting on amazon.com on users' behalf;[^7][^23] Amazon then filed a federal suit in California in November 2025 alleging that Comet disguised itself as a Chrome browser, accessed customer accounts without clearly disclosing agent status, and thereby violated Amazon's terms of service and potentially the Computer Fraud and Abuse Act.[^7][^24] Perplexity's response framed the dispute as "bullying" and asserted that users have the right to "hire" digital assistants.[^25]

The implications for merchants and protocol designers are significant:

1. Identity disclosure becomes non-negotiable. Cloudflare's Web Bot Auth and Visa's Trusted Agent Protocol (see 06) exist precisely to give retailers a cryptographic answer to "is this request a known agent, on whose behalf?" Amazon's suit effectively says: absent that answer, agent traffic is unwelcome.[^22][^26]
2. Large marketplaces can opt out. Unlike individual merchants on Shopify or Etsy, Amazon can credibly refuse to participate and still retain demand. That suggests the universe of agent-reachable inventory will be structurally bimodal: ACP/UCP-native merchants on one side, Amazon (and, plausibly, certain other closed ecosystems) on the other.
3. The precedent matters. If Amazon prevails, it hardens the legal basis for closed-garden refusals industry-wide; if Perplexity prevails, it strengthens the "agent as delegated user" reading that underpins AP2 mandates. (See 10 — Regulation & Compliance.)

7. Grocery and last-mile

Grocery is the vertical where agentic commerce maps most cleanly onto everyday reorder behaviour, and where two U.S. aggregators dominate.

• Instacart × ChatGPT. On 8 December 2025, Instacart launched as one of the first apps inside ChatGPT's new Apps SDK, with in-chat Instant Checkout powered by ACP.[^16][^27] Shoppers can turn recipes into carts against Instacart's 1,800+ retailer network, with fulfilment continuing to sit on Instacart's shopper labour pool. Payments run through Stripe on ACP rails. Status: launched (web first; iOS/Android rolling out).
• DoorDash × ChatGPT and DoorDash × Gemini. DoorDash shipped a ChatGPT integration alongside Instacart in December 2025 for recipe-to-order flows;[^28] in early 2026 DoorDash (and Uber) began piloting fully agentic ordering within Google Gemini, where the agent completes multi-step restaurant and grocery orders without the user entering the DoorDash app.[^29] CEO Tony Xu has publicly argued that the logistics stack — onboarding, menus, routing, delivery SLAs — is the defensible asset, and that DoorDash is indifferent to which agent drives discovery.[^30] Status: launched (ChatGPT) / piloted (Gemini agentic).

The grocery flow illustrates a subtlety for merchants: the retailer of record is often the store chain (e.g., Kroger, Aldi, Publix) rather than the aggregator. Under ACP, Instacart remains MoR for the agent-initiated transaction while passing the fulfilment instruction to the underlying grocer — a pattern that extends naturally to Mirakl's marketplace-of-marketplaces vision.

8. Travel and services: OTAs go agentic

Travel is the vertical that flipped hardest and fastest, because discovery-to-purchase intent is concentrated and the OTAs already have decades of structured inventory.

• Expedia and Booking.com were named as the launch apps for ChatGPT's Apps SDK on 6 October 2025, making them among the first in-chat travel planners.[^17] Both support natural-language search for hotels and flights, real-time pricing, and interactive maps inside ChatGPT.
• Deep-link vs. in-chat booking. In early 2026 OpenAI publicly walked back the ambition of completing bookings end-to-end inside ChatGPT for certain travel categories, preferring to hand users off to the OTA for final checkout.[^31] This reassured OTA investors — Expedia and Booking stocks responded positively — and suggests that, for complex regulated inventory (air, hotel, tours), a hybrid "agent discovers, OTA transacts" pattern is settling in.
• Tripadvisor joined the same Apps SDK wave as Expedia and Booking.[^17]
• Expedia B2B / GenAI APIs. Expedia has also shipped AI-driven B2B APIs covering car rentals, activities, insurance and air inventory, positioning itself as the backend for other agentic travel brands — a "supplier-to-agent" layer analogous to Mirakl's marketplace play.[^32]

Travel thus demonstrates two things: first, agentic surfaces are willing to cede final transaction control back to specialists when stakes are high (implying the market for a "handoff protocol" between agents and existing checkout flows); second, the OTAs retain strategic optionality to sell inventory through multiple agent surfaces simultaneously.

9. Emerging B2B agent-to-merchant flows

Consumer agentic checkout is visible; business procurement agents are where the volumes may ultimately be larger and the tooling is earlier. A few structural pieces are in place:

• PayPal's Agent Toolkit and MCP server (April 2025) expose order creation, invoicing, dispute, catalog and reporting APIs to agent frameworks (OpenAI Agent SDK, Vercel AI SDK, LangChain), which are a natural fit for procurement bots creating purchase orders against catalogs.[^33] See 07 — Wallets & Platforms.
• Stripe Issuing for agents provides virtual cards scoped per-agent with per-transaction limits, enabling B2B agents to execute constrained purchases without sharing corporate card credentials.[^34]
• Visa's Trusted Agent Protocol and Mastercard Agent Pay both treat B2B procurement agents as first-class principals (not just consumer shopping bots) — Agent Pay's partner set explicitly includes IBM watsonx Orchestrate, which is primarily deployed in enterprise procurement.[^21][^22]
• Mirakl Connect is being positioned as a B2B-marketplace-ready surface for agent-driven procurement across Mirakl's 100,000+ merchant base.[^13]

The use cases visible in 2025–2026 are still narrow: indirect spend (office supplies, SaaS renewals, travel), MRO procurement, and same-day replenishment for retail operations. General-purpose agentic procurement — an agent negotiating terms, signing a contract and disbursing funds against an invoice — remains largely speculative and is the subject of much of the x402, ERC-8004 and Skyfire work discussed in 05.

10. Merchant risk and economic impact

Early data is thin but the directional risks for merchants are not hard to enumerate.

Customer-acquisition cost (CAC). The dominant CAC channels of the 2015–2025 era — Google paid search, Meta paid social, Amazon sponsored products — are under pressure from agent-mediated discovery. For merchants who appear in ChatGPT, Gemini or Perplexity answers, CAC can fall materially because the agent delivers pre-qualified intent. For merchants who don't, traffic from classical channels is shrinking. In practice retailers report uneven effects: brand-loyal categories (cosmetics, apparel) hold up; commodity categories (household staples, electronics accessories) are most exposed to agent ranker choices.

Conversion. Where launched, ACP and UCP flows report materially higher checkout completion than mobile web, because payment is already vaulted (Shop Pay, Stripe Link, PayPal, wallet passkeys). Concrete public numbers from retailers are thin at the cut-off, but Etsy's 16% stock move on the ACP announcement was in large part a conversion story.[^3]

Dispute and chargeback rates. The critical unknown. Justt.ai and others have warned that agentic flows raise structurally new chargeback vectors: "I did not authorise my agent to buy that," "the agent bought the wrong SKU," "the agent subscribed me to a service." Because MoR stays with the merchant in both ACP and UCP, the merchant absorbs the first-line chargeback hit until the networks' agentic-liability shifts (Visa Trusted Agent Protocol, Mastercard Agent Pay) clarify allocation.[^35] See 10. Publicly, no network has yet released an agentic chargeback rate benchmark, and the Consumer Bankers Association's 2025 white paper flagged this as the most urgent regulatory gap.[^36]

Margin impact. Three overlapping pressures:

1. Platform take-rate on agent-driven orders (OpenAI, Google).
2. Loss of retail-media revenue for large retailers whose own sponsored-product businesses are disintermediated when agents rank organically.
3. Price transparency pressure, because agents easily compare prices across retailers in ways humans rarely bothered to.

Brand equity and customer lifetime value (CLV). Agent-mediated purchases produce weaker brand memory: shoppers remember that ChatGPT bought them laundry detergent, not which brand. Loyalty enrolment rates drop because the agent, not the retailer, owns the opt-in surface. Retailers are responding by pushing loyalty benefits into the feed itself (UCP's member-pricing primitive; Walmart+, Target Circle, Etsy Insider) so the price the agent sees is already personalised.[^6][^10]

11. Merchants × protocols × status: the reference table

Status values: Launched (production), Piloted (gated production), Announced (press only), — (no public participation).

Merchant / Platform	ACP (OpenAI + Stripe)	UCP (Google + Shopify)	AP2 / Trusted Agent / Agent Pay	Notes
Etsy	Launched (29 Sep 2025)[^4]	Launched (Jan 2026)[^6]	Compatible via Stripe	First ACP merchant; single-item then multi-item.
Shopify (seller base)	Launched, phased (Sep 2025–)[^4]	Launched core collaborator (Jan 2026)[^6]	Visa TAP partner[^22]	Shop Pay is the vault layer.
Walmart / Sam's Club	Launched (14 Oct 2025)[^10]	Launched core collaborator (Jan 2026)[^6]	Ecosystem partner	Also runs own "Sparky" assistant.
Wayfair	— (no public ACP)	Launched core collaborator (Jan 2026)[^6]	Compatible via partners	Furniture / home vertical.
Target	—	Launched core collaborator (Jan 2026)[^6]	—	Circle loyalty in feed.
Best Buy	—	Launched endorsing partner[^6]	—	Also via Mirakl marketplace.
Macy's, Home Depot, Flipkart, Zalando	—	Launched / Announced endorsing partners[^6]	—	Breadth across verticals.
Instacart	Launched (8 Dec 2025)[^16]	—	Stripe payment rail	1,800+ underlying grocers.
DoorDash	Launched (Dec 2025)[^28]	Piloted agentic in Gemini (early 2026)[^29]	—	Also Uber piloting Gemini.
Expedia	Launched (6 Oct 2025, Apps SDK)[^17]	—	—	Handoff-for-booking in some flows.[^31]
Booking.com	Launched (6 Oct 2025, Apps SDK)[^17]	—	—	Same.
Tripadvisor	Launched (Oct 2025, Apps SDK)[^17]	—	—
Perplexity-merchant network (5,000+ via PayPal)	Via PayPal "Instant Buy" (Nov 2025)[^19]	—	PayPal is Mastercard Agent Pay partner[^21]	Comet executes via browser automation.
Mirakl network (Best Buy, Lowe's, Macy's, Carrefour, John Lewis, Ulta)	Piloted via Stripe/OpenAI	Launched endorsing partners via Mirakl Nexus[^13]	—	$15B+ marketplace GMV.
Amazon	—	—	—	Litigating against Perplexity Comet.[^7]
Microsoft Shopping	Agentic checkout piloted	—	Mastercard Agent Pay launch partner[^21]; Visa TAP partner[^22]	Distinct from merchant path.
Apple/Apple Pay merchants	—	—	Compatible via tokenisation	No public agent surface yet.

12. Merchant checklist for adopting agentic checkout

For a retailer planning agentic-channel readiness in 2026, a concise operational checklist:

1. Decide your MoR posture. Confirm you are willing to remain Merchant-of-Record for agent-initiated orders under ACP / UCP. If not, a marketplace MoR (Mirakl, Instacart, a payfac) is the alternative.
2. Harden your product feed. Ship sub-hourly inventory, per-variant pricing, GTIN/MPN hygiene, returns-policy structured data, and member-pricing overlays. Aim for UCP's capability schema, not just schema.org/Product.[^6]
3. Reservation semantics. Implement short-lived inventory holds tied to cart IDs, so an agent can finalise payment without race conditions.
4. Integrate a compatible payments stack. Stripe (ACP), Adyen, Checkout.com, Worldpay, Fiserv, Braintree — all are Visa Trusted Agent Protocol / Mastercard Agent Pay partners.[^21][^22] (See 06, 07.)
5. Adopt agent identity verification. Accept Web Bot Auth signatures and Trusted Agent Protocol requests so you can tell "known agent, on behalf of authenticated shopper" from scraper traffic — and write your WAF rules accordingly. (See 06, 09.)
6. Expose loyalty and member pricing in-feed. Otherwise the agent will route the shopper to whichever merchant surfaces the lowest headline price. Walmart+, Target Circle and Etsy Insider all do this inside UCP.[^6][^10]
7. Adjust chargeback and dispute tooling. Build agent-aware dispute flows that can attach Cart Mandate and Payment Mandate evidence (AP2) or SharedPaymentToken metadata (ACP) to representments. (See 10.)
8. Instrument separately. Tag agent sessions distinctly from human sessions across analytics; measure CAC, AOV, conversion, return rate, chargeback rate, CLV and reorder rate for the agentic cohort in isolation.
9. Plan the MoR-handoff case. For complex / regulated verticals (travel, financial products, prescriptions, alcohol, age-gated goods), design a deep-link path where the agent hands control back to your own checkout — the travel-OTA precedent suggests this is a durable pattern.[^31]
10. Decide your Amazon-style posture. If you believe your brand has independent pull, you can refuse agent traffic you don't like, following Amazon's precedent. If you are a marketplace participant rather than a destination brand, this option is not realistically open.

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Summary

Between September 2025 and April 2026 the agentic channel moved from slide-deck to production for a surprisingly wide slice of U.S. and global retail: Etsy, Shopify's seller base and Walmart under ACP; Shopify, Etsy, Wayfair, Target, Walmart and 20+ endorsing partners under UCP; Instacart and DoorDash in grocery and last-mile; Expedia, Booking.com and Tripadvisor in travel; Mirakl-powered marketplaces across home, beauty and general merchandise. The merchant economics are mixed — new demand surface and higher conversion on one hand, platform fees, brand commoditisation and disclosure-driven legal risk (as Amazon vs Perplexity illustrates) on the other — and the retention of Merchant-of-Record status is the hinge on which adoption turns. Protocols have diverged in scope (ACP is narrower, UCP is full-lifecycle) but converged in philosophy: agents are delegated users, not anonymous bots, and the merchant must verify that before honouring the cart. The winners of the next 12 months will be retailers whose feeds are truly agent-ready, whose loyalty logic lives inside the feed rather than on a lost-to-the-agent website, and whose dispute operations can attach cryptographic mandate evidence to chargebacks.

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Sources

[^1]: OpenAI, "Buy it in ChatGPT: Instant Checkout and the Agentic Commerce Protocol," 29 Sep 2025. https://openai.com/index/buy-it-in-chatgpt/

[^2]: CNBC, "Etsy pops 16% as OpenAI announces ChatGPT Instant Checkout," 29 Sep 2025. https://www.cnbc.com/2025/09/29/chatgpt-instant-checkout-etsy-shopify.html

[^3]: CNBC, "Etsy pops 16% as OpenAI announces ChatGPT Instant Checkout for the U.S.," 29 Sep 2025. https://www.cnbc.com/2025/09/29/chatgpt-instant-checkout-etsy-shopify.html

[^4]: OpenAI, "Buy it in ChatGPT: Instant Checkout and the Agentic Commerce Protocol," 29 Sep 2025. https://openai.com/index/buy-it-in-chatgpt/

[^5]: Stripe, "Agentic Commerce Protocol — Merchant of Record and delegated payments," docs.stripe.com, accessed Apr 2026. https://docs.stripe.com/agentic-commerce/protocol

[^6]: Amit Handa and Ashish Gupta, "Under the hood: Universal Commerce Protocol (UCP)," Google Developers Blog, 11 Jan 2026. https://developers.googleblog.com/under-the-hood-universal-commerce-protocol-ucp/

[^7]: Retail Dive, "Amazon sues Perplexity over AI shopping agents," Nov 2025. https://www.retaildive.com/news/amazon-sues-perplexity-ai-shopping-agents/804871/

[^8]: VentureBeat, "OpenAI debuts new ChatGPT 'buy' button and open source agentic commerce protocol," 29 Sep 2025. https://venturebeat.com/ai/openai-debuts-new-chatgpt-buy-button-and-open-source-agentic-commerce

[^9]: Digital Commerce 360, "ChatGPT debuts checkout experience for Etsy, Shopify merchants," 30 Sep 2025. https://www.digitalcommerce360.com/2025/09/30/chatgpt-debuts-checkout-experience-etsy-shopify-merchants/

[^10]: Walmart Corporate, "Walmart partners with OpenAI to create AI-first shopping experiences," 14 Oct 2025. https://corporate.walmart.com/news/2025/10/14/walmart-partners-with-openai-to-create-ai-first-shopping-experiences

[^11]: CNBC, "Walmart partners with OpenAI on ChatGPT shopping," 14 Oct 2025. https://www.cnbc.com/2025/10/14/walmart-openai-chatgpt-shopping.html

[^12]: CBS News, "Walmart joins ChatGPT to offer online shopping via OpenAI agentic commerce," 14 Oct 2025. https://www.cbsnews.com/news/walmart-chatgpt-online-shopping-ai-openai-agentic/

[^13]: Mirakl, "Mirakl reached $218M ARR (+23%) and launched agentic commerce platform Mirakl Nexus," Mirakl news, 2025. https://www.mirakl.com/news/mirakl-momentum-2025-key-results-launch-mirakl-nexus-agentic-commerce

[^14]: FashionNetwork, "Mirakl turns profitable, banks on agentic commerce," 2025. https://ww.fashionnetwork.com/news/Mirakl-turns-profitable-banks-on-agentic-commerce,1811028.html

[^15]: OpenAI, "Inside Mirakl's agentic commerce vision," customer story. https://openai.com/index/mirakl/

[^16]: Instacart, "Instacart App Launches in OpenAI ChatGPT — First Company to Offer In-Chat Checkout," press release, 8 Dec 2025. https://www.instacart.com/company/pressreleases/instacart-app-launches-in-openai-chatgpt

[^17]: PhocusWire, "ChatGPT brings apps into chat, starting with Expedia and Booking.com," Oct 2025. https://www.phocuswire.com/openai-chatgpt-apps-expedia-booking-tripadvisor

[^18]: Perplexity, "Shop like a Pro," Perplexity Hub blog. https://www.perplexity.ai/hub/blog/shop-like-a-pro

[^19]: PayPal, "PayPal and Perplexity Launch Instant Buy Ahead of Black Friday," PayPal Newsroom, Nov 2025. https://newsroom.paypal-corp.com/2025-11-PayPal-and-Perplexity-Launch-Instant-Buy

[^20]: Payment Expert, "Mastercard and Microsoft team up for AI Agent Pay," 30 Apr 2025. https://paymentexpert.com/2025/04/30/mastercard-microsoft-ai-agent-pay/

[^21]: PayPal Newsroom, "Mastercard and PayPal Join Forces To Accelerate Secure Global Agentic Commerce," 27 Oct 2025. https://newsroom.paypal-corp.com/2025-10-27-Mastercard-and-PayPal-Join-Forces-To-Accelerate-Secure-Global-Agentic-Commerce

[^22]: Visa Investor Relations, "Visa Introduces Trusted Agent Protocol — An Ecosystem-Led Framework for AI Commerce," 14 Oct 2025. https://investor.visa.com/news/news-details/2025/Visa-Introduces-Trusted-Agent-Protocol-An-Ecosystem-Led-Framework-for-AI-Commerce/default.aspx

[^23]: Terms.law, "Amazon vs. Perplexity: When a Cease-and-Desist Letter Calls Your AI a Computer Fraud," 3 Nov 2025. https://terms.law/2025/11/03/amazon-vs-perplexity-when-a-cease-and-desist-letter-calls-your-ai-a-computer-fraud/

[^24]: PPC.land, "Amazon sues Perplexity over covert AI agent access to marketplace," Nov 2025. https://ppc.land/amazon-sues-perplexity-over-covert-ai-agent-access-to-marketplace/

[^25]: Forbes (Martina Castellanos), "Amazon Targets Perplexity's AI Agent — Startup Fires Back, Says Bullying Is Not Innovation," 4 Nov 2025. https://www.forbes.com/sites/martinacastellanos/2025/11/04/amazon-targets-perplexitys-ai-agent-startup-fires-back-says-bullying-is-not-innovation/

[^26]: Cloudflare, "Cloudflare Collaborates With Leading Payments Companies to Secure and Enable Agentic Commerce," 21 Oct 2025. https://www.cloudflare.com/press/press-releases/2025/cloudflare-collaborates-with-leading-payments-companies-to-secure-and-enable-agentic-commerce/

[^27]: TechCrunch, "You can buy your Instacart groceries without leaving ChatGPT," 8 Dec 2025. https://techcrunch.com/2025/12/08/you-can-buy-your-instacart-groceries-without-leaving-chatgpt/

[^28]: Supermarket News, "DoorDash users can now use ChatGPT on app," Dec 2025. https://www.supermarketnews.com/grocery-technology/doordash-users-can-now-use-chatgpt-on-app

[^29]: Retail TouchPoints, "DoorDash, Uber Test Out True Agentic Ordering in Google Gemini," 2026. https://www.retailtouchpoints.com/news/doordash-uber-test-out-true-agentic-ordering-in-google-gemini/617519/

[^30]: Restaurant Business, "Why DoorDash isn't afraid of AI shopping agents," 2025. https://www.restaurantbusinessonline.com/technology/why-doordash-isnt-afraid-ai-shopping-agents

[^31]: The Silicon Review, "OpenAI scales back ChatGPT direct bookings; Expedia, Booking stocks surge," Mar 2026. https://thesiliconreview.com/2026/03/openai-scales-back-chatgpt-bookings-expedia-booking-surge

[^32]: Expedia Group, "Expedia Group expands B2B platform and launches GenAI partnerships," Expedia Newsroom. https://www.expedia.com/newsroom/expedia-group-expands-b2b-platform-and-launches-genai-partnerships/

[^33]: PayPal, "PayPal Brings Together Developers, AI Leaders to Power Agentic Commerce at Dev Days," 29 Apr 2025. https://newsroom.paypal-corp.com/2025-04-29-PayPal-Brings-Together-Developers,-AI-Leaders-to-Power-Agentic-Commerce-at-Dev-Days

[^34]: Stripe, "Stripe and OpenAI — Agentic Commerce Protocol collaboration," Stripe Newsroom, Sep 2025. https://stripe.com/newsroom/news/stripe-and-openai

[^35]: Justt.ai, "Agentic Commerce: Preparing for Chargeback and Fraud Risks," 2025. https://justt.ai/blog/agentic-commerce-chargeback-risk-preparation/

[^36]: Consumer Bankers Association, "CBA Releases White Paper Examining Agentic AI, Consumer Payments, and the Future of Regulation," 2025. https://consumerbankers.com/press-release/cba-releases-white-paper-examining-agentic-ai-consumer-payments-and-the-future-of-regulation/