Hi Will,
You may use AdGroupAdService.get() to get ads' information. Please refer to this guide to see the available fields for this service.
You may also use Ad Performance Report as it ads' information such as Headline, Description. Please refer to this guide and these samples on how to generate AdWords API reports.
However, please note that AdWords API supports only ad types listed here.
Please let me know if you have further concerns.
Regards,
Hiroyuki
Google Ads API Team