@Shilad was working a project that provided semantic related measures as an API. Is that still happening?

I have spent quite a bit of time on this over the past few years. I do have a service that I could make available as an endpoint. HOWEVER, from what I've seen in my projects a much better approach is combining the work of Ellery Wulczyn on navigation vectors (https://meta.wikimedia.org/wiki/Research:Wikipedia_Navigation_Vectors) with the "standard" content-based approaches from Wikipedia.

The navigation vectors can understand "subjective" relationships that are not encoded within the Wikipedia content itself. For example, relationships between books, movies, etc. While Wikipedia's factual information (authors, actors, directors, etc.) doesn't capture this well, navigation patterns seem to.

I think that "shallow" approaches could simply combine the two types of vectors and deep learning approaches (that require access to the underlying session data) could do an even better job. I'm happy to help on these efforts.