Shopify Global Catalog vs eBay Browse API for AI agents
Shopify Global Catalog is a set of Shopify MCP servers that let AI agents search products across all Shopify merchants (Global Catalog) or within one store (Storefront Catalog), with cart and checkout tools, built on the Universal Commerce Protocol (UCP). eBay Browse API is eBay's Buy API for searching live eBay listings by keyword or category and fetching item details.
The short answer
- Shopify Global Catalog: AI agents that want to search many independent Shopify stores at once and hand the shopper a real merchant checkout link.
- eBay Browse API: Approved eBay partners who want live new and used eBay listings with affiliate tracking.
Side by side
| Shopify Global Catalog | eBay Browse API | |
|---|---|---|
| Searches | Products across the whole Shopify ecosystem by text, image or similar-product IDs, with filters such as price, shop, shipping and category; or one merchant's catalog at https://{storedomain}/api/ucp/mcp. | Live eBay listings by keyword and category (plus image search in some markets), and item details by item ID. |
| Returns | Results grouped by Universal Product ID with offers from multiple merchants; get_product returns pricing and the seller's checkout link for the chosen variant. | A subset of item details per search hit (more with the EXTENDED field group); full details come from getItem using the item ID. |
| Before the first call | No API key: every request must reference a hosted UCP agent profile. Higher limits and checkout completion need a credential from Shopify's Dev Dashboard (Token tier); anonymous traffic shares one limit and is not for production. | An eBay developer account (sandbox is open to anyone); production use of the Buy APIs is for eBay partners and needs an application through the eBay Partner Network, approved by business model. |
| Free | No key needed, and its pages state no price | Not stated on its pages |
| Acting on a result | Checkout link to the merchant's own checkout (one per store); agents at the highest trust tier can complete checkout through the Checkout MCP. | Affiliate links through the eBay Partner Network (production apps must implement affiliate tracking); eBay member checkout via the separate checkout_session resource needs extra approval. |
| Coverage | Not stated on its pages | 16 eBay marketplaces: AT, AU, BE, CA, CH, DE, ES, FR, GB, HK, IE, IT, NL, PL, SG and US (image search only in US, DE, UK and AU). |
| MCP server | Official Global Catalog MCP at https://catalog.shopify.com/api/ucp/mcp; per-store Storefront Catalog MCP at https://{storedomain}/api/ucp/mcp. | 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 Shopify Global Catalog?
No API key: every request must reference a hosted UCP agent profile. Higher limits and checkout completion need a credential from Shopify's Dev Dashboard (Token tier); anonymous traffic shares one limit and is not for production.
Is Shopify Global Catalog free?
No key needed, and its pages state no price.
What do I need before I can use eBay Browse API?
An eBay developer account (sandbox is open to anyone); production use of the Buy APIs is for eBay partners and needs an application through the eBay Partner Network, approved by business model.
Is eBay Browse 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.
Shopify Global Catalog, read on October 15, 2026:
- shopify.dev/docs/agents/catalog/global-catalog: “The Global Catalog MCP server enables AI agents to search and discover products across the entire Shopify ecosystem”
- shopify.dev/docs/agents/catalog/global-catalog: “Results are clustered by Universal Product ID (UPID) and include offers from multiple merchants.”
- shopify.dev/docs/agents/catalog/global-catalog: “pricing and seller checkout links for the buyer's chosen variant”
- shopify.dev/docs/agents/catalog/global-catalog: “The `/api/ucp/mcp` endpoint requires an agent profile.”
- shopify.dev/docs/agents/catalog/storefront-catalog: “enables AI agents to search and discover products from a single merchant's catalog”
- shopify.dev/docs/agents: “Higher trust tiers unlock broader access, including direct checkout completion.”
- shopify.dev/docs/agents/profiles/auth-and-rate-limiting: “Agents authenticating with a credential issued through Dev Dashboard”
- shopify.dev/docs/agents/profiles/auth-and-rate-limiting: “The default limit is 5 requests each second for each API client.”
- shopify.dev/docs/agents/profiles/auth-and-rate-limiting: “Don't use unauthenticated requests for production traffic.”
eBay Browse API, read on October 15, 2026:
- developer.ebay.com/api-docs/buy/static/api-browse.html: “Using the Browse API, you can create a rich selection of items for your buyers to browse with keyword and category searches.”
- developer.ebay.com/api-docs/buy/static/api-browse.html: “For each item found, a subset of the item details is returned.”
- developer.ebay.com/api-docs/buy/static/buy-requirements.html: “The use of eBay’s Buy APIs in production is intended for eBay partners only.”
- developer.ebay.com/api-docs/buy/static/buy-requirements.html: “You must apply for production access through the eBay Partner Network.”
- developer.ebay.com/api-docs/buy/static/buy-requirements.html: “Acceptance of applications is based on the proposed business model”
- developer.ebay.com/api-docs/buy/static/buy-requirements.html: “Application must implement affiliate tracking details (needed for revenue share capability)”
- developer.ebay.com/api-docs/buy/static/buy-requirements.html: “To use the checkout_session resource, which supports eBay member checkout, you need approval.”