  In this paper, we study the capped vertex functions associated to certain
zero-dimensional type-$A$ Nakajima quiver varieties. The insertion of
descendants into the vertex functions can be expressed by the Macdonald
operators, which leads to explicit combinatorial formulas for the capped vertex
functions.
  We determine the monodromy of the vertex functions and show that it coincides
with the elliptic R-matrix of symplectic dual variety. We apply our results to
give the vertex functions and the characters of the tautological bundles on the
quiver varieties formed from arbitrary stability conditions.
