In the Ads view, click the Edit ad button on the ad's row. For responsive search ads (RSAs), you can edit the headlines (minimum 3, maximum 15) and descriptions (minimum 2, maximum 4), keep or adjust the pinned position of each text, and change the final URL. For Demand Gen video ads, the modal shows Headlines (1 to 5), Long headlines (1 to 5) and Descriptions (1 to 5). Click Save and the change is applied directly to the existing ad, without creating a new one. Other ad formats (such as Display ads or the ads inside Performance Max campaigns) can't be edited through the Google API, and the modal tells you when an ad isn't editable. Tip: each field has a character counter so you can stay within Google's limits.