Minimum liquid to make solid dough
This is actually not answerable as an absolute.  One of the Great Unknowns when baking with flour is how humid it has been in your flour storage recently, and thus how much water is already in the flour.  I've had a few cups of flour require as much as half a cup extra water to get the right consistency depending on the season.


My usual approach for making the driest dough I can is to instead of pre-measuring, add the liquid gradually to a spinning food processor that contains the dry ingredients.  It will lump up quite quickly when the liquid is right.