If your account is configured to utilize Personalized Search & Merchandising, this endpoint is required to feed into the feature. In the integration, the moment the data points for "shopper", "cart", or "lastViewed" query string parameters are assigned a value, a Preflight request will need to be sent before a request to the Autocomplete or Search API endpoint is sent. The GET method will support up to 2048 characters, if there are more characters use the POST method.

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