As of version 2020-01, the Collect resource no longer works with smart collections. For more information, see Migrating to the collection endpoint.
The Collect resource connects a product to a custom collection.
Collects are meant for managing the relationship between products and custom collections. For every product in a custom collection there is a collect that tracks the ID of both the product and the custom collection. A product can be in more than one collection, and will have a collect connecting it to each collection. Unlike many Shopify resources, collects aren't apparent to store owners.
Collects are for placing products in custom collections only. Smart collections use rules to determine which products are their members. Creating a collect that links a product to a smart collection r