diff --git a/python/langsmith/evaluation/evaluator.py b/python/langsmith/evaluation/evaluator.py
index fc1f07685..3a11fd292 100644
--- a/python/langsmith/evaluation/evaluator.py
+++ b/python/langsmith/evaluation/evaluator.py
@@ -667,15 +667,17 @@ async def awrapper(
                     "example": example,
                     "inputs": example.inputs if example else {},
                     "outputs": run.outputs or {},
-                    "attachments": {
-                        name: {
-                            "presigned_url": value["presigned_url"],
-                            "reader": io.BytesIO(value["reader"].getvalue()),
+                    "attachments": (
+                        {
+                            name: {
+                                "presigned_url": value["presigned_url"],
+                                "reader": io.BytesIO(value["reader"].getvalue()),
+                            }
+                            for name, value in (example.attachments or {}).items()
                         }
-                        for name, value in (example.attachments or {}).items()
-                    }
-                    if example
-                    else {},
+                        if example
+                        else {}
+                    ),
                     "reference_outputs": example.outputs or {} if example else {},
                 }
                 args = (arg_map[arg] for arg in positional_args)
diff --git a/python/tests/integration_tests/test_client.py b/python/tests/integration_tests/test_client.py
index 8e3e5cd8d..28a38602b 100644
--- a/python/tests/integration_tests/test_client.py
+++ b/python/tests/integration_tests/test_client.py
@@ -1490,10 +1490,10 @@ async def test_aevaluate_with_attachments(langchain_client: Client) -> None:
 
     examples = [
         ExampleUploadWithAttachments(
-            inputs={"question": "What is shown in the image?"},
+            inputs={"question": "What is shown in the image?", "index": i},
             outputs={"answer": "test image"},
             attachments={
-                "image": ("image/png", b"fake image data for testing"),
+                "image": ("text/plain", bytes(f"data: {i}", "utf-8")),
             },
         )
         for i in range(10)
@@ -1508,16 +1508,16 @@ async def target(
         assert "image" in attachments
         assert "presigned_url" in attachments["image"]
         image_data = attachments["image"]["reader"]
-        assert image_data.read() == b"fake image data for testing"
+        assert image_data.read() == bytes(f"data: {inputs['index']}", "utf-8")
         return {"answer": "test image"}
 
     async def evaluator_1(
-        outputs: dict, reference_outputs: dict, attachments: dict
+        inputs: dict, outputs: dict, reference_outputs: dict, attachments: dict
     ) -> Dict[str, Any]:
         assert "image" in attachments
         assert "presigned_url" in attachments["image"]
         image_data = attachments["image"]["reader"]
-        assert image_data.read() == b"fake image data for testing"
+        assert image_data.read() == bytes(f"data: {inputs['index']}", "utf-8")
         return {
             "score": float(
                 reference_outputs.get("answer") == outputs.get("answer")  # type: ignore
@@ -1525,12 +1525,12 @@ async def evaluator_1(
         }
 
     async def evaluator_2(
-        outputs: dict, reference_outputs: dict, attachments: dict
+        inputs: dict, outputs: dict, reference_outputs: dict, attachments: dict
     ) -> Dict[str, Any]:
         assert "image" in attachments
         assert "presigned_url" in attachments["image"]
         image_data = attachments["image"]["reader"]
-        assert image_data.read() == b"fake image data for testing"
+        assert image_data.read() == bytes(f"data: {inputs['index']}", "utf-8")
         return {
             "score": float(
                 reference_outputs.get("answer") == outputs.get("answer")  # type: ignore