Identify the systems already responsible for an order
Start with an existing successful customer purchase. Write down where the product is stored, which service calculates the final total, which provider processes payment and which system delivers the item. An agent channel must connect to these responsibilities. It does not remove the need for them.
Imagine a merchant selling an illustrative $29 research download. The store already creates an order, records payment and grants access. A useful agent integration preserves that path and adds a reliable way for the buyer's assistant to discover the edition, obtain current terms and complete an authorized purchase. A second disconnected order database would make support harder even if its first demo looks simple.
Agentic commerce platforms can package several of these jobs, but the package name is not an ownership map. A catalog connector can distribute offers without controlling checkout. A payment gateway can fund an order without handling fulfilment. A commerce channel can host the customer's interaction while the merchant remains responsible for what was sold and delivered.
Platform and channel ownership
Scroll the table to compare all columns.
| Platform and surface | Discovery | Checkout and protocol | Eligibility to verify | Payment and fulfillment owner | Implementation path |
|---|---|---|---|---|---|
| Shopify + ChatGPT | Shopify Catalog | Referral to store checkout; no native purchase implied | Eligible store/products and active channel | Existing store payment and fulfillment configuration | Shopify channel guide ↗ |
| Shopify + Google, Copilot or Meta | Applicable platform catalog/channel route | Shopify-powered in-channel checkout when activated | Channel-specific direct-checkout conditions | Inspect Shopify/store payment and post-purchase setup | Shopify channel configuration ↗ |
| WooCommerce + Google | Google for WooCommerce catalog sync | Discovery does not establish checkout support | Google feed/product eligibility; actual extension versions | Store payment and delivery extensions | WooCommerce compatibility guide ↗ |
| WooCommerce + Stripe agentic checkout | Planned Suite catalog route in Woo documentation | Official Woo page says coming soon; no enabled checkout inferred | Connector release and account eligibility unresolved | Verify supported extension and store ownership | Track official extension documentation ↗ |
| Custom store + selected surface | Merchant catalog behind an adapter | Implement chosen ACP/UCP contract or supported embedded path | Protocol implementation and channel onboarding are separate | Explicit adapters to merchant payment/order services | Custom-store integration guide ↗ |
Shopify starts with platform and channel controls
Shopify's current agentic storefront documentation describes products reaching AI channels through Shopify Catalog and, for Google surfaces, the relevant Google channel or Merchant Center route. Merchants manage channels in the Agentic area of their Shopify admin. These platform controls are a useful starting point because they connect channel choices to the store's existing catalog and order operations. [1]
Checkout location differs by channel. Shopify describes ChatGPT as a discovery-focused referrer whose customer finishes at the merchant's store checkout. It describes Shopify-powered direct checkout for Google AI Mode and Gemini, Microsoft Copilot and Meta when direct checkout is activated and the relevant conditions apply. Treat that distinction as a dated channel fact, not a permanent promise about every AI assistant. [1]
Your evaluation should therefore include the real store configuration. Check eligible products, supported destinations and any restrictions shown in the platform's current help and admin. Test the customer path with a permitted item. Do not infer a store's eligibility from the existence of a public protocol specification or another merchant's announcement.
WooCommerce separates extensions from the core store
With WooCommerce, examine the extensions that publish products and process the order. The official agentic commerce page describes Google catalog synchronization and discusses agentic checkout integrations with their own release status. As checked on October 8, 2026, its Stripe for WooCommerce section describes agentic checkout as coming soon. A merchant should not treat an installed Stripe payment extension as proof that every advertised agent checkout path is enabled. [2]
List your active payment, tax, shipping and access-control extensions before choosing a connector. An integration that handles a simple product may need additional work for subscriptions, bundles or personalized downloads. Ask which extension owns the order, how it applies existing hooks and what happens when payment succeeds but a downstream delivery extension fails.
A staging purchase can reveal those boundaries without making assumptions about them. Use a safe test route supported by the provider, compare the store's calculated total with the agent-facing total and inspect the resulting order. Record which integration versions were evaluated. This recommended test method does not imply that this guide has tested your store or a named third-party connector.
A custom storefront needs a clear adapter boundary
For a custom store, the main decision is where to expose commerce capabilities. Keep your catalog and order services authoritative, and place a channel or protocol adapter in front of them. The adapter translates requests and responses; it should not invent a separate price calculation or quietly bypass inventory checks.
UCP is modular and describes capabilities across the commerce journey. Google documents native and embedded integration paths for its UCP experience. Those options help frame the technical work, while Google's onboarding and supported surface requirements remain a separate question. Implementing a standard is not an automatic admission ticket to a distribution channel. [3] [4]
The custom path gives you control over product-specific behavior, but you also own recovery and ongoing compatibility. Budget for status retrieval, changed terms, duplicate completion attempts, event verification and support tooling. A small adapter is easier to maintain when the underlying business services expose these responsibilities clearly.
Where checkout runs
- Referral route
The AI surface links to a merchant-controlled checkout.
- Channel checkout route
The customer completes a supported checkout within the channel experience.
- Merchant order
Both routes need an authoritative order tied to the payment result.
- Post-purchase service
The responsible merchant team delivers the item and resolves exceptions.
Compare operational fit before feature lists
Use the same scenario for every option: the research download, a known buyer, a bounded approval and a delivery result. Ask how each route publishes the product, obtains the total, collects authority, records payment and returns access. Where the answer is missing, mark it unknown instead of awarding a positive score for a marketing phrase.
Country and product coverage need specific evidence. Request the exact supported seller location, buyer location, currency and product category for your intended route. A payment provider's general geographic reach does not establish availability of its agentic commerce product. An open protocol's design also does not establish commercial onboarding eligibility.
Cost comparisons should follow the same discipline. Separate platform charges, payment processing, channel charges and any service fees that actually apply. Use current provider terms and your own projected order mix. This guide does not publish a universal cheapest platform because an eligible referral route and a fully integrated native checkout can have different cost structures and operational responsibilities.
Choose the smallest change that supports a complete purchase
If your current platform has a supported channel that fits your product and location, evaluate that path before replacing the store. If you need a specialized digital entitlement or custom workflow, inspect whether an adapter can preserve the existing checkout and delivery services. A platform migration creates its own operational work and is not a prerequisite for every agent purchase.
Then use the platform-specific guide and the readiness checklist to turn the comparison into an implementation plan. Assign unresolved questions to the catalog, checkout, payment or fulfilment owner. A useful platform decision ends with an accountable route from a current offer to a delivered order, rather than a long list of acronyms.