I'm unclear on this point from the documentation. Is it possible to give Solr X document IDs and tell it that I want documents similar to those?
Example:
I am not clear about sending the document IDs, nor whether MoreLikeThis can operate on multiple documents as in this example.
you can try passing multiple Ids with the Query q=id:(document_id1 OR document_id2 OR document_id3)
:-
e.g.
http://localhost:8080/solr/select/?qt=mlt&q=id:(document_id1 OR document_id2 OR document_id3)&mlt.fl=[field1],[field2],[field3]&fl=id&rows=10