This is probably a very easy answer, but Google's documentation is not helpful in detailing what to expect with ads.
I am updating a site from the old paid GSS (since it will soon be phased out), and transitioning them to Google CSE. If we use the JSON/Atom API, will ads be displayed? Google is insistent on telling you that CSE is free because they display ads, but it's not clear if ads show up when using/paying for search queries through the JSON API.
Thanks!
In case anyone is trying to find the answer to this in the future, the answer is no; ads do not display by default when results are pulled using the JSON API.
This is pretty much what I expected since the ads themselves would have to be pulled from JSON, and we're not pulling in any ads. This means that sites that need the CSE but don't want Ads can get around it by implementing their search with the API. You just have to keep the query limit in mind and pay if you expect more than 100/day.
Alternatively, if you qualify as a non-profit, you can follow the prompts in the CSE control panel to register as such and implement the CSE with the provided script as usual without any ads or branding.