Here are the current links to the documentation around integrating subscriptions:
- https://shopify.dev/docs/themes/ajax-api/reference/cart
- https://shopify.dev/docs/admin-api/graphql/reference/products-and-collections
- https://shopify.dev/docs/themes/liquid/reference/objects/selling-plan
However, there is nothing outlined as far as how to integrate the new subscriptions feature with the Storefront API or API documentation.
Is the Storefront API not going to support the ability to add Subscriptions to checkout or has the Shopify team just not created documentation yet?