Relating Berkovits and $A_\infty$ Superstring Field Theories; Small Hilbert Space Perspective

In a previous paper it was shown that the recently constructed action for open superstring field theory based on $A_\infty$ algebras can be re-written in Wess-Zumino-Witten-like form, thus establishing its relation to Berkovits' open superstring field theory. In this paper we explain the relation between these two theories from a different perspective which emphasizes the small Hilbert space, and in particular the relation between the $A_\infty$ structures on both sides.