Yes and no. But even for cases, where the algorithm is not published, the general approach can be indicated and hence "Ask them where on Wikipedia you can read

Yes and no. But even for cases, where the algorithm is not published, the general approach can be indicated and hence "Ask them where on Wikipedia you can read more about the approach they took" might be still valid. For ex. you can say you are using a seq2seq model but you don't have to disclose the precise architecture, preprocessing, optimizations and other training nuances.