All product pages should contain the product tagging. The product tagging can be the entire metadata or only a small subset of it.
The product tagging is used to pass the context of the current product being viewed which in turn is used to personalise the recommendations e.g. cross-sellers, and commonly also periodically crawled by Nosto to build an index.
You can tag your product pages in two different ways:
Tagging all the metadata (Recommended): This approach is the recommended way to tag your product pages. It contains the entirety of the product metadata and leverages the crawler to build a 1:1 replica of your catalog.
Tagging the bare minimum: This approach entails tagging just the product-id and requires you to leverage an API to build a 1:1 replica of your catalog. This is an advanced use-case and requires that your account-manager disables crawling for your website.