App Insights auth fixes and other customer integrations

Author: ggailey777

articles/azure-functions/functions-app-settings.md

@@ -58,19 +58,16 @@ Don't use both `APPINSIGHTS_INSTRUMENTATIONKEY` and `APPLICATIONINSIGHTS_CONNECT
 
 ## APPLICATIONINSIGHTS_AUTHENTICATION_STRING
 
-The connection string for Application Insights by using Microsoft Entra authentication. Use this setting when you must connect to your Application Insights workspace by using Microsoft Entra authentication. For more information, see [Microsoft Entra authentication for Application Insights](../azure-monitor/app/azure-ad-authentication.md).
+Enables access to Application Insights by using Microsoft Entra authentication. Use this setting when you must connect to your Application Insights workspace by using Microsoft Entra authentication. For more information, see [Microsoft Entra authentication for Application Insights](../azure-monitor/app/azure-ad-authentication.md).
 
-  - For system-assigned identity:
+When you use `APPLICATIONINSIGHTS_AUTHENTICATION_STRING`, the specific value that you set depends on the type of managed identity:
 
-       | App setting    | Value    |
-       | -------------- |--------- |
-       | APPLICATIONINSIGHTS_AUTHENTICATION_STRING         | `Authorization=AAD`    |
+| Managed identity | Setting value |
+| ----- | ----- |
+| System-assigned | `Authorization=AAD` |  
+| User-assigned | `Authorization=AAD;ClientId=<USER_ASSIGNED_CLIENT_ID>` |
 
-   - For user-assigned identity:
-
-       | App setting   | Value    |
-       | ------------- | -------- |
-       | APPLICATIONINSIGHTS_AUTHENTICATION_STRING         | `Authorization=AAD;ClientId={Client id of the User-Assigned Identity}`    |
+This authentication requirement is applied to connections from the Functions host, snapshot debugger, profiler, and any language-specific agents. To use this setting, the managed identity must already be available to the function app, with an assigned role equivalent to [Monitoring Metrics Publisher](/azure/role-based-access-control/built-in-roles/monitor#monitoring-metrics-publisher). 
 
 [!INCLUDE [functions-app-insights-disable-local-note](../../includes/functions-app-insights-disable-local-note.md)]