YouCompleteMe will be better than TabNine for API exploration.
TabNine will be more reliable (it will work correctly with malformed, ill-typed, or half-written code) and it can find patterns in your code, like you can see in the pictures on the website.
TabNine will be more reliable (it will work correctly with malformed, ill-typed, or half-written code) and it can find patterns in your code, like you can see in the pictures on the website.