Users A user is anyone who can be offered items on any of your channels. We offer two ways to identify users in our API’s: user_id: a user ID is a permanent ID for a user, that can be used to identify the same user across different devices. A common example is a login ID. device_id: a device ID is an ID assigned to a user on a specific device. A device ID should change as little as possible. A common example is a permanent cookie ID tied to the user’s browser, or an app ID. Every event/recommendation call to Froomle should contain at least a device_id, and as soon the user establishes a more permanent ID, both device_id and user_id. If users can surf your website before establishing a more permanent ID, every device should be assigned a device ID. If users cannot surf your website before establishing a permanent ID, only a user_id is required. If users cannot establish a permanent ID, only the device_id is sufficient. For privacy/GDPR reasons, we do not want any additional information beyond the user_id and device_id. The passed identifier should never contain personally identifiable information, such as a name or an email address. How we handle devices and users When serving recommendations for a given user (user_id,device_id or both) we will use all history we have available. We illustrate this with some examples based on the information passed in your recommendation request: User ID Device ID Effect Yes Yes Everything that was recorded for this user’s login, as well as everything registered under the device will be used as history to inform the user’s recommendations. Yes No Everything that was recorded for this user’s login will be used as history to inform the user’s recommendation. If the user browsed your website on this device before login, this will not be taken into account as no device_id was passed. No Yes Everything that was recorded on this device will be used as history to inform the user’s recommendation. If a user previously browsed your website on other devices, this will not be taken into account as no user_id was passed. No No No recommendations can be made. Anonymous users For users that browse anonymously (no-consent for GDPR, cookie policy, or other reasons), we support the following procedure: Recommendation Requests: Request anonymous recommendations, this way we can still provide you with recommendations (typically popular items and/or based on the context item) for these users without you sharing their browsing history. Send us the "user_group":"anonymous" in your request Use a single "device_id":"no-consent" for all users We will exclude anonymous requests from the performance metrics. User Events: We prefer that you send us web events for opted-out users, in an anonymous way. Send the events with "user_group":"anonymous" in your event so we can make sure these events do not deteriorate the quality of our models. Use a single "device_id":"no-consent" for all users We will exclude anonymous events from the performance metrics. Alternatively you can choose to not send us any recommendation requests or events for these users at all.