If you use Varnish or another full-page cache mechanism, you must exclude certain Nosto blocks (hole punching).
Nosto adds query parameters to the product URLs for tracking purposes. You may encounter a cache-miss when query parameters are appended to the URL. We recommend modifying your VCL definition to automatically strip out the query parameters added by Nosto.
Magento CE does not ship with a built-in FPC mechanism and you must manually exclude two Nosto blocks. Failure to do so may result in sensitive information leaking across browser sessions.
Note: The plugin uses a feature called hashed cookie identifiers (HCID) to safeguard against the leakage of customer information on Nosto's end.
If you are using Magento EE's built-in FPC mechanism, you need not worry about hole punching as hole-punching rules are auto-configured.