[1.19.22 Adobe Target Community Q&A Coffee Break Answer provided by @jontehero:
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Hi @strrjms,
I appreciate your question. We have a great article on basing recommendations on a recommendation key for custom criteria: https://experienceleague.adobe.com/docs/target/using/recommendations/criteria/base-the-recommendatio...
In short, you can pass in basically any alpha-numeric key and then just make sure that that key is in the first row of the custom algorithm csv. I also like to add the key to the "excluded" list to make sure it never gets recommended.
Regarding Recs QA: In order to preview results for Recently viewed or user based recommendations criteria, you will need to first browse the site outside of QA mode, then use the same session to open a QA mode link: https://experienceleague.adobe.com/docs/target/using/recommendations/recommendations-activity/previe...
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