The services are regular HomeAssistant services - you can call them from automations, or you can test them by going (in your HA instance) to Developer Tools / Actions.
Just type “anova” in the “Action” box, and you will see the available services/actions.
The integration does not appear to be working with the newer Anova Precision Oven 2.0 - the returned payload is different than the one that has been put in the source code.
The good news is that I have been able to write a script to have the oven start and read the parameters - I will try to fork the repository by @andrew.tupitsin and send a pull request
Here is a draft pull request with the required changes to get the integration to read all the data correctly. Still working on in, but I am making some progress: Required changes for Anova Precision Oven V2 by XVincentX · Pull Request #60 · andr83/hacs-anova-oven · GitHub
For the people interested - I have kept working into this during the weekend and modified the code to now also work in order to send commands according to the new API. I have done some basic tests and I am satisfied with what I see 
I’d be willing to discuss - if somebody can help me out to test it with the v1 oven - a way to make this integration work with both ovens, so I do not have to keep “my” version around.
Let me know if that’s something that’d work for you, and we can discuss!
BTW, a recent update to the Anova Oven app added a section for API tokens in settings (“personal access tokens”).
Yes, and it also seems like they released the new documentation portal. I will try to take some time and modify the integration to use the new token - and go from there!