diff --git a/src/nlsat/nlsat_solver.cpp b/src/nlsat/nlsat_solver.cpp
index 97cac90fc..00fc58962 100644
--- a/src/nlsat/nlsat_solver.cpp
+++ b/src/nlsat/nlsat_solver.cpp
@@ -2034,6 +2034,10 @@ namespace nlsat {
             m_assignment.reset();
         }
 
+        lbool check(literal_vector& assumptions, assignment const& rvalues, polynomial_ref_vector& core) {
+            return l_undef;
+        }
+
         lbool check(literal_vector& assumptions) {
             literal_vector result;
             unsigned sz = assumptions.size();
@@ -4104,6 +4108,10 @@ namespace nlsat {
         return m_imp->check(assumptions);
     }
 
+    lbool solver::check(literal_vector& assumptions, assignment const& rvalues, polynomial_ref_vector& core) {
+        return m_imp->check(assumptions, rvalues, core);
+    }
+
     void solver::get_core(vector<assumption, false>& assumptions) {
         return m_imp->get_core(assumptions);
     }
diff --git a/src/nlsat/nlsat_solver.h b/src/nlsat/nlsat_solver.h
index ae403fc83..0d0a0d3d4 100644
--- a/src/nlsat/nlsat_solver.h
+++ b/src/nlsat/nlsat_solver.h
@@ -218,6 +218,17 @@ namespace nlsat {
 
         lbool check(literal_vector& assumptions);
 
+        // check satisfiability of asserted formulas relative to assumptions.
+        // produce either,
+        // l_true - a model is availabe (rvalues can be ignored) or,
+        // l_false - update the list of assumptions (possibly reset it to empty), and a set of polynomials in core,
+        // such that the conjunction of the assumptions and the polynomials in core is unsatisfiable.
+        // l_undef - if the search was interrupted by a resource limit.
+        // We associate literals with the polynomials in the core based on their sign with respect to rvalues.
+        // If p(rvalues) > 0, then the literal is p <= 0, p(rvalues) < 0, then p(rvalues) >= 0, and p(rvalues) = 0, then p != 0.
+        //
+        lbool check(literal_vector& assumptions, assignment const& rvalues, polynomial_ref_vector& core);
+
         // -----------------------
         //
         // Model