Shopify Global Catalog vs Etsy Open 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). Etsy Open API is Etsy's REST API for listings, shops, inventory and orders on the Etsy marketplace.
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.
- Etsy Open API: Searching handmade, vintage and craft listings from independent Etsy sellers.
Side by side
| Shopify Global Catalog | Etsy Open 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. | All active Etsy listings (findAllListingsActive, with keyword search), plus shops and shop listings. |
| 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. | Listing records including title, price and the full URL of the listing page on Etsy. |
| 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. | A registered app with an API keystring and shared secret; apps used beyond your own shop go through review (Personal App), and wider use needs a separately approved Commercial Access request. Searching active listings needs only the API key, not OAuth. |
| 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. | Buy link: each listing has its Etsy page URL; buying happens on Etsy. |
| Coverage | Not stated on its pages | The Etsy marketplace (sellers worldwide). |
| 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. | Etsy Dev MCP server at https://mcp.api.etsycloud.com/mcp, but it only teaches an assistant the API docs and schemas; it does not call the Etsy API or return listings. |
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 Etsy Open API?
A registered app with an API keystring and shared secret; apps used beyond your own shop go through review (Personal App), and wider use needs a separately approved Commercial Access request. Searching active listings needs only the API key, not OAuth.
Is Etsy Open 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.”
Etsy Open API, read on October 15, 2026:
- developer.etsy.com/documentation: “a REST API that extends support for inventory, sales orders, and shop management on the Etsy platform”
- developer.etsy.com/documentation: “Registering an app creates an Etsy App API keystring and a shared secret.”
- developer.etsy.com/documentation: “Personal Apps go through a deeper review process than Seller Apps.”
- developer.etsy.com/documentation: “You must have an approved Personal App before you can request Commercial Access.”
- etsy.com/openapi/generated/oas/3.0.0.json: “A list of all active listings on Etsy paginated by their creation date.”
- etsy.com/openapi/generated/oas/3.0.0.json: “The full URL to the listing's page on Etsy.”
- developer.etsy.com/documentation/essentials/rate-limits: “You can see your application's current rate limits in the”
- developer.etsy.com/documentation/mcp_server/devmcpserver: “Use the Etsy Dev MCP server to teach your AI assistant how to use the Etsy Open API.”
- developer.etsy.com/documentation/mcp_server/devmcpserver: “It does not call the Etsy API directly.”