Google is implementing AI content labels across various platforms, including Google Ads, Merchant Center, and Ads Editor. This feature lets advertisers label assets as AI-generated or AI-edited to comply with the recently published help page guidance.
Here’s a screenshot of Asset Studio showing the AI label as a column that can be toggled on or off:

The latest version of the Google Ads Editor also supports this feature:
The AI label column indicates whether the labeling has been activated in your account. Ads utilizing assets with the AI label set to “on” will display an accompanying icon, along with a disclosure wherever the ad appears.
This rollout aims to enhance transparency regarding AI-generated content in advertising.
This update was spotted by Hana Kobzová.