Walmart Affiliate API vs OpenAI Agentic Commerce Protocol for AI agents
Walmart Affiliate API is Walmart I/O's set of REST services for affiliates to search Walmart.com products and earn referral fees. OpenAI Agentic Commerce Protocol is an open checkout protocol (with Stripe) and OpenAI's specs for merchants to send product feeds to ChatGPT and accept orders from it.
The short answer
- Walmart Affiliate API: Affiliate publishers in the Impact network who want live Walmart.com prices and availability with tracked links.
- OpenAI Agentic Commerce Protocol: Merchants who want their products indexed and sold inside ChatGPT; it gives other agents no product catalog to search.
Side by side
| Walmart Affiliate API | OpenAI Agentic Commerce Protocol | |
|---|---|---|
| Searches | Text search of the Walmart.com catalogue for items sold online, item lookup by item ID or UPC, taxonomy, reviews, trending items and recommendations; several categories are excluded. | – |
| Returns | Item data including real-time price and availability; a responseGroup parameter sets which item fields come back. | – |
| Before the first call | A Walmart.com account to log in to walmart.io, a registered application with an uploaded public key (which creates a consumer ID), and an Impact Radius publisher ID passed on calls. | For merchants: approval to onboard product feeds into ChatGPT (application at chatgpt.com/merchants), then a product feed and checkout endpoints that ChatGPT calls. |
| Acting on a result | Affiliate links: calls carry your Impact Radius publisher ID and you earn referral fees when shoppers buy on Walmart.com. | Checkout through the protocol: the merchant implements checkout-session endpoints that an agent calls, and stays the seller; OpenAI is not the merchant of record. |
| Coverage | Walmart.com (United States). | – |
| MCP server | No official server listed | – |
Where Openpath fits
Openpath has no products listed yet. Sellers can list a product on Openpath today, free, and agents will find it through the same search as jobs and businesses. Get listed.
Questions people ask
What do I need before I can use Walmart Affiliate API?
A Walmart.com account to log in to walmart.io, a registered application with an uploaded public key (which creates a consumer ID), and an Impact Radius publisher ID passed on calls.
Is Walmart Affiliate API free?
Its pages listed no free use when we read them on October 15, 2026.
Sources
Every line about another company comes from its own pages. Prices and terms change, so check the source before you rely on one.
Walmart Affiliate API, read on October 15, 2026:
- walmart.io/apidocs/affiliates/introduction: “a useful collection of RESTful services that allow developers to earn referral fees”
- walmart.io/apidocs/affiliates/introduction: “Several categories are excluded from the API calls.”
- walmart.io/apidocs/affiliates/affiliate-marketing-api: “Perform text search on the Walmart.com catalogue and get matching items available for sale online.”
- walmart.io/apidocs/affiliates/affiliate-marketing-api: “Get real time item status including price and availability”
- walmart.io/apidocs/affiliates/affiliate-marketing-api: “Your Impact Radius Publisher Id”
- walmart.io/apidocs/affiliates/quickstart: “After the public key is uploaded, consumer id will be created for your application.”
OpenAI Agentic Commerce Protocol, read on October 15, 2026:
- developers.openai.com/commerce/guides/get-started: “Onboarding product feeds in ChatGPT is currently available to approved partners.”
- developers.openai.com/commerce/guides/key-concepts: “OpenAI is not the merchant of record in the Agentic Commerce Protocol.”
- agenticcommerce.dev: “Stripe and OpenAI developed the Agentic Commerce Protocol.”
- agenticcommerce.dev: “Any AI agent can call an ACP-enabled checkout.”