Google Sends Shoppers Back to the Store: Cart Transfer, a YouTube Agent and AI Traffic Reports

Google has started rolling out cart transfer in Merchant Center: a shopper who assembled a cart right inside Google can now finish the order on the merchant's own site instead of inside Google. Search Engine Journal reports this, citing a holiday shopping post by Ashish Gupta, Google's VP and GM of Merchant Shopping. Alongside cart transfer, Google opened a beta of a branded agent in YouTube ads and expanded its AI traffic report to five countries.

For a store owner this matters more than the headline suggests. Since January, Google has been building the Universal Commerce Protocol, a set of rules under which its search and AI mode show the product, assemble the cart and take the payment on their own. In that scheme the merchant risks becoming a warehouse behind someone else's storefront. The new options are the first visible concession in the other direction: the shopper can be brought back to you.

For now all of this works in the United States, with Australia and Canada promised next. But the logic behind these decisions applies to any store whose products are sold through third-party platforms, and in Russia and the CIS that is almost every store.

What UCP Is and Why Merchants Were Unhappy

The Universal Commerce Protocol, or UCP, is the way Google connects a merchant's products to its services so that a purchase happens without a visit to the site. According to Search Engine Journal, direct checkout through UCP is already available to hundreds of thousands of brands and retailers across Google. Together with the protocol, Business Agent went live in Search on January 12: a branded assistant that answers shoppers' questions on the store's behalf.

That same January, merchants explained what they disliked. The publication quotes one retailer: customers never visit the store, they see accessory suggestions from other sellers, and they feel less connected to the brand. Put simply, the sale happened, but the customer did not: no return visit, no upsell, no recognition.

Cart transfer is the answer to those complaints. The shopper assembles items in Google, clicks a button and lands on the merchant's checkout page with the cart already filled. From there they are in your environment: your related products, your loyalty program, your subscription form.

How Cart Transfer Works

In the developer documentation the capability is called Transfer to merchant cart. To enable it, the merchant has to support the Cart API: accept requests from Google with the cart contents and turn them into a cart on their own site. Search Engine Journal notes that the capability itself is not new: a draft description appeared in March, and in May, in its Google Marketing Live post, the company said shoppers would be able to transfer items to the merchant's site. Now it is a setup option that a merchant with hub access chooses as part of Merchant Center validation.

There is a separate checklist for those who only need transfer: it skips full product feed setup, product warnings and customer support details. In other words, the path for a store that does not want to hand Google the full payment cycle is shorter than the one for complete checkout inside Google.

The same Merchant Center section has a sandbox where you can test how the site responds to the cart and checkout requests Google will send. This is useful because an error at the seam between two systems looks to the shopper like “I clicked the button and nothing happened”, and the shopper will blame the store, not Google.

The onboarding order, as the publication describes it: complete the technical setup, submit an interest form and wait for Google to select the account for hub access. The hub is opening gradually, first in the U.S.; Australia and Canada follow early next year.

Analytics: From the Buy Button to Payment

Google promises to add analytics to the UCP hub. The documentation, updated September 3, describes a UCP Analytics Reporting dashboard in the same Merchant Center tab. It is available to merchants with UCP enabled and the Performance role, and it shows the shopper's path from clicking the Buy button to completing the purchase, along with average order value, cancellations, account linking information and the top-selling UCP products. This data is not yet available through the Merchant API.

Search Engine Journal does not claim the dashboard is already live: merchants who have the UCP integration tab are invited to check for themselves whether an Analytics tab has appeared in it.

It is important to understand how this dashboard differs from the second report discussed in the publication, AI performance insights. That report shows share of voice, frequency and which products appear in AI answers. The UCP dashboard starts where the report ends: from the click on the Buy button through to the purchase. One measures visibility, the other measures sales.

The AI Traffic Report: What It Has and What It Lacks

The AI performance insights report in Merchant Center is now open to merchants in Australia, Canada, India, New Zealand and the U.S. Google's post calls it generally available, but the help page clarifies: the report works only for English-language queries in those five countries, covers organic AI traffic only and lists no click metric.

The publication recalls that in July, when the report was being tested on select U.S. accounts, it suggested which product attributes to fill in but did not show whether AI Mode had sent anyone to the site. That has not changed. The merchant sees that their product is being shown, but not whether anyone clicks through.

For a store this means one simple thing: the report is useful for understanding whether products get into AI answers at all, and for tightening up product listings. It cannot be used to judge revenue.

The Store's Agent in YouTube Ads

The third piece of news is a beta program for Business Agent in YouTube ads, U.S. only for now. Merchants who qualify and sign up get a branded agent right inside their video ads: viewers can browse products and ask questions without leaving YouTube. The qualification criteria and the length of the beta are not specified in the publication.

The point is the same as with cart transfer, only from the other side: Google is embedding the conversation with the store wherever the person already is. The question “do you have it in another colour?” is asked of the ad itself, not of a contact form that still has to be found on the site.

What This Means for a Store in Russia and the CIS

Neither cart transfer, nor the YouTube agent, nor the expanded report works in Russia yet: the publication talks about the U.S., Australia, Canada, India and New Zealand. A merchant in Yekaterinburg gets no direct benefit from the new buttons in Merchant Center. But there are three conclusions that apply to them right now.

First. Google has confirmed the direction: purchases increasingly happen where the shopper asked the question, in search, in an AI answer, in a video. The store's site is becoming not a storefront but the point where the deal is completed, and the shopper still has to be brought there. Marketplaces and aggregators here work on the same logic, and merchants' complaints about them sound the same: the customer is not ours, there is no upsell, the brand is not remembered.

Second. The only things in this scheme that belong to the merchant are the product data and their own checkout page. Google has, in effect, offered merchants a deal: give us a complete and accurate feed, and we will send the shopper back to you with a ready cart. Whoever shows up with a poor feed is not admitted to the deal. This applies to any platform that takes your products through a feed and to any AI assistant that recommends products based on their descriptions.

Third. Analytics will have to be assembled piece by piece. Even at Google the two reports do not line up: one counts impressions, the other counts purchases, and clicks appear in neither. Do not expect a single “from impression to money” dashboard from someone else's platform; it has to be built on your side.

What to Do This Week

• Check the product feed as a document, not as an export: full names, attributes, availability, prices, photos. This is what AI assistants and aggregators will use to show you, and this is what Google relies on when transferring a cart.
• Make sure the cart on your site can accept items from outside: via a link with parameters or through the store's programming interface. If a shopper arrives from a platform with a product already chosen, they should not have to find it again.
• Set up separate tags in your site analytics for visits from platforms and AI services, and count checkouts by them, not just visits.
• Collect the questions shoppers ask before buying and answer them in the product listings. Agents like Business Agent answer from your own data: what is not in the listing is not in the answer either.
• If the store sells to the U.S., Canada or Australia through Google Merchant Center, submit the interest form for the UCP hub and use the sandbox to test how the site responds to cart requests.

Conclusion

Since January, Google has been building a scheme in which the merchant is needed only as a supplier of goods and a recipient of payment, and now it has begun sending the shopper back, through cart transfer, an agent in ads, and reports. The reason is not generosity: without merchants who benefit from taking part, the protocol will gather neither products nor sales. For a store this is a hint about what to hold on to. The feed, the checkout page and your own analytics are three things you cannot hand over to a platform, because those are exactly what the platform will later ask you for.