As well as Tomas' link I think there are another a couple of possibilities with published API info.
So I've been taking part in the Exoclock project. They have a really nice scheduler to help you pick which transits would be available from your location and with your equipment and they are building a database of verified observations.
You can access that database programtically and there are even python code snippets for doing that here www.exoclock.space/database/planets