Role of short distance behavior in off-shell open-string field theory

A recent proposal for a background-independent open-string field theory is studied in detail for a class of backgrounds that correspond to general quadratic boundary interactions on the world sheet. A short distance cutoff is introduced to formulate the theory with a finite number of local and potentially unrenormalizable boundary couplings. It is shown that renormalization of the boundary couplings makes both the world-sheet partition function and the string field action finite and cutoff independent, although the resulting string field action has an unpalatable dependence on the leading unrenormalizable coupling.