diff --git a/ollama/_utils.py b/ollama/_utils.py
index 15f1cc0c..d0449dc7 100644
--- a/ollama/_utils.py
+++ b/ollama/_utils.py
@@ -60,7 +60,7 @@ def convert_function_to_tool(func: Callable) -> Tool:
     func.__name__,
     (pydantic.BaseModel,),
     {
-      '__annotations__': {k: v.annotation if v.annotation != inspect._empty else str for k, v in inspect.signature(func).parameters.items()},
+      '__annotations__': {k: v.annotation if v.annotation != inspect._empty else str for k, v in inspect.signature(func).parameters.items() if v.kind not in (inspect.Parameter.VAR_POSITIONAL, inspect.Parameter.VAR_KEYWORD)},
       '__signature__': inspect.signature(func),
       '__doc__': parsed_docstring[doc_string_hash],
     },
diff --git a/tests/test_utils.py b/tests/test_utils.py
index cb9e0d4f..295fb08c 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -230,6 +230,20 @@ def no_types(a, b):
   assert tool['function']['parameters']['properties']['b']['type'] == 'string'
 
 
+def test_function_with_varargs():
+  def func_with_varargs(x: int, *args, **kwargs) -> int:
+    """
+    A function with varargs.
+    Args:
+        x: The first number
+    """
+    return x
+
+  tool = convert_function_to_tool(func_with_varargs).model_dump()
+  assert set(tool['function']['parameters']['properties']) == {'x'}
+  assert tool['function']['parameters']['required'] == ['x']
+
+
 def test_function_with_parentheses():
   def func_with_parentheses(a: int, b: int) -> int:
     """