Hi Dale,
Thank you for reaching out. Smart Campaigns are currently not supported in the Google Ads API which is the reason why you are not able to get details on spend data or other metrics. A feature request has been put in place for this, but we do not have a timeline for when it will be available. For any updates on this, please keep an eye out on our
blog.
Regards,
Danica, Google Ads API Team

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