Merge pull request #7698 from segmentio/journeys-v2-observability

Add section on observability in V2 Journeys [DOC-1080]

Author: pwseg

src/engage/journeys/event-triggered-journeys.md

@@ -120,7 +120,44 @@ Segment built Event-Triggered Journeys to respond instantly to events, offering
 - **Editing and versioning**: After you publish an event-triggered journey, you won't be able to edit it. To modify a journey, create a new journey. 
 - **Real-time delivery**: Event-Triggered Journeys aim for an expected delivery time of under 5 minutes from the moment an event is performed to when the payload reaches the destination, assuming there is no delay step in the journey. However, external factors outside of Segment's control may occasionally introduce latency.
 
-## Use Cases
+## Observability
+
+Segment provides built-in tools to help you understand how users move through your journeys. These features let you debug issues, verify behavior, and review step-by-step activity for individual users.
+
+### Profile explorer: Journeys tab
+
+From Profile explorer, you can view the journeys a user entered. For Event-Triggered Journeys (V2), you’ll see the total number of times the user has entered each journey; V1 journeys display only the current step.
+
+To access Profile explorer:
+
+1. From your Segment workspace, go to **Unify > Profile explorer** and open a user profile.
+2. Click the **Journeys** tab.
+
+### Journey instance timeline
+
+When you need to understand how a specific user moved through a journey, the Journey Instance Timeline shows a detailed, step-by-step view of the user’s path.
+
+This view is useful for troubleshooting, testing, or verifying behavior after launch. You’ll see the exact sequence of events and timing for a single journey instance. Follow these steps to access the instance timeline:
+
+- **Option 1**:
+  1. Open a user profile from the Profile explorer.
+  2. Click the **Journeys** tab, then click the name of the journey.
+- **Option 2**:
+  1. From your Segment workspace, go to **Engage > Journeys**, then open the **Overview** tab.
+  2. Use the **Search for a profile** field to look up the user by email or ID.
+  3. Select a journey instance to view its full timeline.
+
+### Profile activity
+
+Use the **Profile activity** tab on the journey overview page to see a high-level log of entries, exits, and transitions across all users. This is helpful for filtering activity by time, user, or step, especially when you want to confirm how different users have moved through a journey.
+
+Follow these steps to access Profile activity:
+
+1. Go to **Engage > Journeys**.
+2. Select a journey and click the **Profile activity** tab.
+3. Use the filters to narrow down the results by user, time range, event type, or step name.
+
+## Use cases
 
 Event-Triggered Journeys can power a variety of real-time, personalized experiences. This section details some common scenarios to help you see how they might work in practice.