diff --git a/replicate/client.py b/replicate/client.py
index 3e767d6..a808e63 100644
--- a/replicate/client.py
+++ b/replicate/client.py
@@ -26,6 +26,7 @@
 from replicate.exceptions import ReplicateError
 from replicate.file import Files
 from replicate.hardware import HardwareNamespace as Hardware
+from replicate.helpers import FileOutput
 from replicate.model import Models
 from replicate.prediction import Predictions
 from replicate.run import async_run, run
@@ -160,19 +161,65 @@ def webhooks(self) -> Webhooks:
         """
         return Webhooks(client=self)
 
+
+    @overload
     def run(
         self,
         ref: str,
         input: Optional[Dict[str, Any]] = None,
         *,
-        use_file_output: Optional[bool] = True,
+        use_file_output: None = None,
         **params: Unpack["Predictions.CreatePredictionParams"],
-    ) -> Union[Any, Iterator[Any]]:  # noqa: ANN401
+    ) -> Union[FileOutput, List[FileOutput]]: ...
+
+    @overload
+    def run(
+        self,
+        ref: str,
+        input: Optional[Dict[str, Any]] = None,
+        *,
+        use_file_output: True,
+        **params: Unpack["Predictions.CreatePredictionParams"],
+    ) -> Union[FileOutput, List[FileOutput]]: ...
+
+    @overload
+    def run(
+        self,
+        ref: str,
+        input: Optional[Dict[str, Any]] = None,
+        *,
+        use_file_output: False,
+        **params: Unpack["Predictions.CreatePredictionParams"],
+    ) -> Union[str, List[str]]: ...
+
+    def run(
+        self,
+        ref: str,
+        input: Optional[Dict[str, Any]] = None,
+        *,
+        use_file_output: Optional[bool] = None,
+        **params: Unpack["Predictions.CreatePredictionParams"],
+    ) -> Union[Union[str, FileOutput], List[Union[str, FileOutput]]]:
         """
         Run a model and wait for its output.
-        """
 
-        return run(self, ref, input, use_file_output=use_file_output, **params)
+        Args:
+            ref: The reference identifier for the model to run.
+            input: Optional input data for the model.
+            use_file_output: If False, returns strings. If True or None (default), returns FileOutput objects.
+            **params: Additional parameters for prediction creation.
+
+        Returns:
+            If use_file_output is True or None (default):
+                - Single prediction: FileOutput
+                - Multiple predictions: List[FileOutput]
+            If use_file_output is False:
+                - Single prediction: str
+                - Multiple predictions: List[str]
+        """
+        # If use_file_output is None, we treat it as True
+        effective_use_file_output = True if use_file_output is None else use_file_output
+        return run(self, ref, input, use_file_output=effective_use_file_output, **params)
 
     async def async_run(
         self,