The short answer on ACP and the 4% query
The Agentic Commerce Protocol is documented by OpenAI as a commerce integration framework. OpenAI’s current materials say that building with ACP is open to all, while product-feed onboarding and Instant Checkout in ChatGPT are currently for approved partners. The official materials reviewed on August 28, 2026 do not publish a 4% merchant fee.
That distinction matters. A search result or an old article can be useful historical context, but it is not a current fee schedule. Do not use a 4% claim in a merchant plan, a pricing model or a public guide without a current first-party source that applies to the exact integration.
What OpenAI currently documents
Product discovery and feeds
OpenAI says merchants can provide structured product feeds so ChatGPT can index product data and present accurate information in shopping experiences. The feed documentation covers product identity, descriptions, pricing, inventory, media and fulfillment data. OpenAI’s March 24 announcement also says that leading retailers including Target, Sephora, Nordstrom, Lowe’s, Best Buy, The Home Depot and Wayfair have ACP discovery integrations.
For Shopify merchants, the same announcement says Shopify Catalog already integrates product data into ChatGPT, with no extra work required from individual merchants for that catalog path. This does not prove eligibility for every partner feature.
Checkout and payments
The current checkout specification defines create, update, complete, cancel and retrieve checkout-session endpoints. It also documents merchant order events and payment processing on the merchant’s existing systems. The key concepts guide explains that a merchant remains responsible for order acceptance, fulfillment options, tax, risk decisions and payment processing.
Instant Checkout in ChatGPT is currently described as available to approved partners. It is therefore inaccurate to describe ACP checkout as universally available, universally closed or automatically enabled for every Shopify store.
What a merchant can verify today
- Confirm whether the store is eligible for Shopify’s current Agentic surface in Shopify Admin.
- Confirm whether Shopify Catalog already represents the relevant product data.
- Compare visible product data with the information supplied to catalog, feed or integration paths.
- Keep product titles, variants, price, availability, delivery and return information current.
- If applying for an OpenAI feed or checkout integration, follow the current OpenAI onboarding and conformance requirements rather than a third-party checklist.
- Keep payment, tax, fulfillment and order handling on the merchant’s documented stack.
ACP, Shopify Catalog and direct checkout are different questions
| Question | What the reviewed official documentation supports |
|---|---|
| Can a merchant build with ACP? | OpenAI says the protocol is open to build with. |
| Is product-feed onboarding automatic? | No. OpenAI describes it as available to approved partners. |
| Are Shopify products represented in ChatGPT? | OpenAI says Shopify Catalog already integrates Shopify product data for the catalog path. |
| Is Instant Checkout available to every merchant? | No. OpenAI describes it as available to approved partners. |
| Is a 4% fee currently documented by OpenAI? | No current official fee schedule was found in the reviewed OpenAI materials. |
How to use an ACP readiness assessment responsibly
An ACP readiness assessment can check whether a store exposes coherent product facts and whether its checkout, policies and data are technically reviewable. It cannot certify partner approval, predict product placement, set a fee or promise checkout availability. Those outcomes depend on current program decisions and merchant-specific commercial terms.
Related guides
- Sell on ChatGPT with Shopify
- Shopify AI visibility: optimize your store
- Perplexity Shopping for Shopify
- Schema.org for Shopify
- Robots.txt and AI crawlers
In short: treat ACP as a documented integration path, verify each merchant’s current eligibility and rely on official documents for feed, checkout and pricing claims.