cook rye

Hi,

in many recipes I read the cooking is required to be made "undercover", that is with the pan enveloped in aluminum foil, while in others the envelope is not required and generally a much higher temperaturae is used.

I noticed that when I don't cover the pan the bread comes out with a gummy and tough crust, that I consider really annoying; moreover the crumb comes out lighter and less sweet.

I'd like to have some advise on the cooking method to use; at the moment I'm relying just on luck and on past experience rather than on a methodology.