add-to-cart
Add a product to cart on any UCP-enabled Shopify store and get a checkout URL. Requires a variant ID from the search-catalog or get-product-details results. Returns the cart contents, checkout URL, and a cart_id token. To build multi-item carts: pass the returned cart_id back on subsequent calls. The agent holds the cart_id — no server-side session needed. Example: domain: "allbirds.com", variantId: "gid://shopify/ProductVariant/12345" Multi-item: domain: "allbirds.com", variantId: "...", cartId: "gid://shopify/Cart/abc123"
Input Schema
{
"type": "object",
"required": [
"domain",
"variantId"
],
"properties": {
"cartId": {
"type": "string",
"description": "Cart token from a previous add-to-cart call. Pass this to add more items to an existing cart instead of creating a new one."
},
"domain": {
"type": "string",
"description": "The store domain (e.g., \"allbirds.com\")"
},
"country": {
"type": "string",
"description": "ISO country code for localized pricing/checkout (e.g., \"US\", \"GB\", \"CA\"). Optional."
},
"quantity": {
"type": "integer",
"description": "Quantity to add (default: 1)"
},
"variantId": {
"type": "string",
"description": "The product variant ID from search-catalog results (e.g., \"gid://shopify/ProductVariant/12345\")"
}
}
}
Stores exposing the add-to-cart tool
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