Will user id pass with every event in client side implementation

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Based on the knowledge sources provided, I can answer your question about whether the user ID will pass with every event in a client-side implementation of Mixpanel.In a client-side implementation using Mixpanel's SDKs, the user ID (referred to as $user_id in Mixpanel) will not automatically pass with every event. Instead, it depends on whether the user is in an identified (logged-in) or anonymous state.Here's how it works: 1. For anonymous users (before login): - Mixpanel's SDKs automatically generate a $device_id and attach it to all events. - The $device_id serves as an anonymous identifier for the user.2. For identified users (after login): - You need to call the .identify(<user_id> ) method when a user logs in or signs up. - After calling .identify(), subsequent events will include the $user_id.3. When a user logs out: - You should call the .reset() method, which clears the local storage and generates a new $device_id for the session.This behavior is described in the Identifying Users (Simplified) documentation: > Any events prior to calling .identify are considered anonymous events. Mixpanel's SDKs will generate a $device_id to associate these events to the same anonymous user. By calling .identify(<user_id> ) when a user signs up or logs in, you're telling Mixpanel that $device_id belongs to a known user with ID user_id.To ensure that the user ID passes with every event after login, you should: 1. Call .identify(<user_id> ) when the user logs in or signs up. 2. Call .reset() when the user logs out.By following these steps, you'll ensure that events are properly attributed to users in both anonymous and identified states.

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