I am an existing TestNG user with Automate. Do I need to use the SDK to be able to use Test Observability?

Yes, you’d need to integrate with the BrowserStack SDK in the language/framework that you use. But, having said that, you need not use the SDK to run your Automate/App Automate tests, to be able to use Test Observability.

Consider the following example: You run tests on BrowserStack Automate using your own CI setup without any BrowserStack SDK. Now, to use Test Observability, you’ll need to use the BrowserStack SDK but you need not make any other changes to your test setup. You can simply achieve that by setting browserstackAutomation: false in the browserstack.yml config file of SDK.