Walmart Affiliate API vs Google Shopping 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. Google's commerce developer tools are for sellers: Merchant API manages a merchant's own Merchant Center products, and UCP on Google lets merchants sell inside AI Mode in Search and Gemini.
The short answer
- Walmart Affiliate API: Affiliate publishers in the Impact network who want live Walmart.com prices and availability with tracked links.
- Google Shopping: Merchants who want their products shown and sold in Google Shopping, AI Mode and Gemini, not developers who want to search products.
Side by side
| Walmart Affiliate API | Google Shopping | |
|---|---|---|
| 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. | Merchant API needs a Merchant Center account and a Google Cloud project; UCP on Google is joined through a waitlist. |
| Acting on a result | Affiliate links: calls carry your Impact Radius publisher ID and you earn referral fees when shoppers buy on Walmart.com. | Nothing for outside agents; UCP checkout happens inside Google's own AI Mode and Gemini. |
| 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.”
Google Shopping, read on October 15, 2026:
- developers.google.com/merchant/api/overview: “The Merchant API enables automation of account, product, and inventory management within Merchant Center”
- developers.google.com/merchant/ucp: “Adopt UCP to enable agentic actions on AI Mode in Google Search and Gemini, starting with direct buying.”
- developers.google.com/merchant/ucp: “You remain the Merchant of Record.”
- developers.google.com/merchant/ucp: “Join the waitlist”
- developers.google.com/custom-search/v1/overview: “The Custom Search JSON API is closed to new customers.”
- developers.google.com/custom-search/v1/overview: “Existing Custom Search JSON API customers have until January 1, 2027 to transition to an alternative solution.”