diff --git a/__init__.py b/__init__.py
index 9794310..65affdf 100644
--- a/__init__.py
+++ b/__init__.py
@@ -36,6 +36,16 @@ class SimpleStringRepository(io.ComfyNode):
             ],
         )
 
+    @classmethod
+    def fingerprint_inputs(cls, **kwargs):
+        # Force re-execution when any random selector is set to -1 (auto-random)
+        for i in range(1, 6):
+            r = kwargs.get(f"random{i}", -1)
+            t = kwargs.get(f"target{i}", 0)
+            if t and r == -1:
+                return float("nan")  # always re-run
+        return None  # normal caching
+
     @classmethod
     def execute(cls, string, delimiter, target1, strength1, random1,
                 target2, strength2, random2, target3, strength3, random3,
@@ -121,6 +131,16 @@ class SimpleStringRepositoryCompact(io.ComfyNode):
             ],
         )
 
+    @classmethod
+    def fingerprint_inputs(cls, **kwargs):
+        # Force re-execution when any random selector is set to -1 (auto-random)
+        for i in range(1, 6):
+            r = kwargs.get(f"random{i}", -1)
+            t = kwargs.get(f"target{i}", 0)
+            if t and r == -1:
+                return float("nan")  # always re-run
+        return None  # normal caching
+
     @classmethod
     def execute(cls, string, delimiter, target1, target2, target3, target4, target5):
         raw = [target1, target2, target3, target4, target5]