Looking at bread recipes most just say add X amount of starter but they do not specify at what hydration. Also they do not specify where the flour and water are to come from. I just found one for a 100% rye bread that says specifically that the flour for the levain is to come out of the total but the water is separate and to just add "some" to make a thick sloppy liquid. Since the levain can be a very significant part of total final volume I find all this a bit problematic.
Are there standard definitions and methods I do not know about? Are the water and flour for the levain usually over and above the amounts for given in the recipe? Usually taken from the total recipe so hydration does not much matter? What?
Thank you for any insights!