Nope. Flakes are only mentioned in a handful of places in the official docs and almost always as "this accepts flake as input". Never as something you should try using (even the format is not explained).
OK, to be more accurate when I say "documentation" I really mean "widespread online messaging about Nix". At least everywhere I've looked, existing Nix users advocate for starting with flakes now on the basis that it will be the new normal soon.