diff --git a/nemoguardrails/colang/v2_x/runtime/eval.py b/nemoguardrails/colang/v2_x/runtime/eval.py
index 4c5998e8c..1d76266f7 100644
--- a/nemoguardrails/colang/v2_x/runtime/eval.py
+++ b/nemoguardrails/colang/v2_x/runtime/eval.py
@@ -40,20 +40,11 @@ class ComparisonExpression:
     """An expression to compare to values."""
 
     def __init__(self, operator: Callable[[Any], bool], value: Any) -> None:
-        if not isinstance(value, (int, float)):
-            raise ColangValueError(
-                f"Comparison operators don't support values of type '{type(value)}'"
-            )
         self.value = value
         self.operator = operator
 
     def compare(self, value: Any) -> bool:
         """Compare given value with the expression's value."""
-        if not isinstance(value, type(self.value)):
-            raise ColangValueError(
-                "Comparing variables of different types is not supported!"
-            )
-
         return self.operator(value)
 
 
@@ -168,6 +159,7 @@ def eval_expression(expr: str, context: dict) -> Any:
                 "greater_than": _greater_than_operator,
                 "equal_greater_than": _equal_or_greater_than_operator,
                 "not_equal_to": _not_equal_to_operator,
+                "is_in": _is_in,
                 "list": list,
             }
         )
@@ -286,6 +278,11 @@ def _not_equal_to_operator(v_ref: Any) -> ComparisonExpression:
     return ComparisonExpression(lambda val, val_ref=v_ref: val != val_ref, v_ref)
 
 
+def _is_in(v_ref: Any) -> ComparisonExpression:
+    """Create a is in comparison expression."""
+    return ComparisonExpression(lambda val, val_ref=v_ref: val in val_ref, v_ref)
+
+
 def _flows_info(state: State, flow_instance_uid: Optional[str] = None) -> dict:
     """Return a summary of the provided state, or all states by default."""
     if flow_instance_uid is not None and flow_instance_uid in state.flow_states: