Is it expected that a caster casting counterspell doesn’t know what spell their enemy is casting?

@JeremyECrawford Is it expected that a caster casting counterspell doesn’t know what spell their enemy is casting nor what level it is cast at?

— SlyFlourish (@SlyFlourish) December 2, 2017

When a monster casts a spell, some DMs say what spell is being cast and some DMs don’t. Either approach is fine. The rules assume magic is mysterious, and you don’t know what’s being cast. By extension, counterspell gives you no special knowledge when you cast it. #DnD https://t.co/RlOWNVQAcI

— Jeremy Crawford (@JeremyECrawford) December 3, 2017