Using a custom recommend client - Should addAlgoliaAgent be an optional method?

[PaulWild]

Hi,

For reasons, we are looking at creating a backend recommend client using a similar pattern as described for instant search.

This is an example that does work for our needs:

 const recommendClient = () => ({
    async getRelatedProducts(requests) {
      ...call to backend
    },
    addAlgoliaAgent() {}
  });

I have two questions:

1. Is this ok to do? It's not documented like the instantSearch
2. The fact the we have to overload another method doesn't feel great. Looking at the instantSearch codebase this function was made optional. Could this be done in this package? (Im happy to raise a MR if so)