karust

The search is indeed free. But if you try to automate the process, it becomes "paid" :) For instance, I use it as part of my other solution. To inspect the content of URLs I find during some queries.

Not yet, I have to do some research with this one

Ahah, no, that's mostly for small researchers like me. Creating a startup around it would be difficult, with questionable financial capabilities.

Lately I've been struggling to get search engine results via API. If you ever had the same situation, this project might help you