diff --git a/nanobot/utils/helpers.py b/nanobot/utils/helpers.py
index bb0f5e55..99863c33 100644
--- a/nanobot/utils/helpers.py
+++ b/nanobot/utils/helpers.py
@@ -130,8 +130,10 @@ def strip_think(text: str) -> str:
     return text.strip()
 
 
-def strip_reasoning_tags(text: str) -> str:
+def strip_reasoning_tags(text: object) -> str:
     """Remove wrapper tags from text that is already known to be reasoning."""
+    if not isinstance(text, str):
+        return ""
     text = re.sub(r"^\s*<(?:think|thinking|thought)/>\s*", "", text)
     text = re.sub(r"\s*<(?:think|thinking|thought)/>\s*$", "", text)
     text = re.sub(r"^\s*<(?:think|thinking|thought)>\s*", "", text)
diff --git a/tests/utils/test_strip_think.py b/tests/utils/test_strip_think.py
index cbcc65f5..351c1ca6 100644
--- a/tests/utils/test_strip_think.py
+++ b/tests/utils/test_strip_think.py
@@ -327,3 +327,6 @@ class TestStripReasoningTags:
         assert strip_reasoning_tags("Preparing final response</thinking>") == (
             "Preparing final response"
         )
+
+    def test_non_string_reasoning_ignored(self):
+        assert strip_reasoning_tags(object()) == ""