diff --git a/arcaflow_plugin_opensearch/opensearch_plugin.py b/arcaflow_plugin_opensearch/opensearch_plugin.py
index 587392a..f5ac38d 100644
--- a/arcaflow_plugin_opensearch/opensearch_plugin.py
+++ b/arcaflow_plugin_opensearch/opensearch_plugin.py
@@ -8,11 +8,29 @@
 from opensearch_schema import (
     ErrorOutput,
     SuccessOutput,
+    BulkUploadList,
+    BulkUploadObject,
     DocumentRequest,
+    DataList,
     bulk_upload_object_schema,
 )
 
 
+@plugin.step(
+    id="process_list",
+    name="Process List",
+    description="Process list input into a bulk_upload_list",
+    outputs={"success": BulkUploadList, "error": ErrorOutput},
+)
+def process_list(
+    params: DataList,
+) -> typing.Tuple[str, typing.Union[BulkUploadList, ErrorOutput]]:
+    bulk_upload_list = []
+    for item in params.data_list:
+        bulk_upload_list.append(BulkUploadObject(params.operation, item))
+    return "success", BulkUploadList(bulk_upload_list)
+
+
 @plugin.step(
     id="opensearch",
     name="OpenSearch",
@@ -47,7 +65,7 @@ def process_bulk_list_generator():
             doc = item[1]
             # Append the global metadata to the document
             if params.metadata:
-                doc.update(params.metadata)
+                doc["metadata"] = params.metadata
             yield doc
 
     if params.username:
@@ -89,4 +107,4 @@ def process_bulk_list_generator():
 
 
 if __name__ == "__main__":
-    sys.exit(plugin.run(plugin.build_schema(store)))
+    sys.exit(plugin.run(plugin.build_schema(store, process_list)))
diff --git a/arcaflow_plugin_opensearch/opensearch_schema.py b/arcaflow_plugin_opensearch/opensearch_schema.py
index f22b019..72decab 100644
--- a/arcaflow_plugin_opensearch/opensearch_schema.py
+++ b/arcaflow_plugin_opensearch/opensearch_schema.py
@@ -4,7 +4,7 @@
 from arcaflow_plugin_sdk import schema, validation, plugin
 
 
-class Operation(enum.Enum):
+class OperationType(enum.Enum):
     CREATE = "create"
     DELETE = "delete"
     INDEX = "index"
@@ -12,7 +12,7 @@ class Operation(enum.Enum):
 
 
 @dataclass
-class BulkUploadOperationMeta:
+class OperationMeta:
     _index: typing.Annotated[
         typing.Optional[str],
         schema.name("index"),
@@ -29,15 +29,19 @@ class BulkUploadOperationMeta:
 
 
 @dataclass
-class BulkUploadObject:
+class Operation:
     operation: typing.Annotated[
-        # typing.Dict[Operation, BulkUploadOperationMeta],
+        # typing.Dict[OperationType, BulkUploadOperationMeta],
         # Temporarily changing the key to a string in order to work
         # around a workflow validation failure for the enum as a key
-        typing.Dict[str, BulkUploadOperationMeta],
+        typing.Dict[str, OperationMeta],
         schema.name("operation"),
         schema.description("The operation type and associated operation metadata."),
     ]
+
+
+@dataclass
+class BulkUploadObject(Operation):
     data: typing.Annotated[
         typing.Dict[str, typing.Any],
         schema.name("data"),
@@ -49,7 +53,16 @@ class BulkUploadObject:
 
 
 @dataclass
-class DocumentRequest:
+class BulkUploadList:
+    bulk_upload_list: typing.Annotated[
+        typing.List[BulkUploadObject],
+        schema.name("bulk upload list"),
+        schema.description("The list of objects for the bulk upload operation."),
+    ]
+
+
+@dataclass
+class DocumentRequest(BulkUploadList):
     url: typing.Annotated[
         str,
         schema.name("url"),
@@ -61,11 +74,6 @@ class DocumentRequest:
         schema.name("index"),
         schema.description("Name of the default index that will receive the data."),
     ]
-    bulk_upload_list: typing.Annotated[
-        typing.List[BulkUploadObject],
-        schema.name("bulk upload list"),
-        schema.description("The list of objects for the bulk upload operation."),
-    ]
     metadata: typing.Annotated[
         typing.Optional[typing.Dict[str, typing.Any]],
         schema.name("metadata"),
@@ -97,6 +105,15 @@ class DocumentRequest:
     ] = True
 
 
+@dataclass
+class DataList(Operation):
+    data_list: typing.Annotated[
+        typing.List[typing.Any],
+        schema.name("data list"),
+        schema.description("List of data object to process into the bulk_upload_list."),
+    ]
+
+
 @dataclass
 class SuccessOutput:
     message: str
diff --git a/tests/unit/test_arcaflow_plugin_opensearch.py b/tests/unit/test_arcaflow_plugin_opensearch.py
index 26d61eb..ae79dd4 100644
--- a/tests/unit/test_arcaflow_plugin_opensearch.py
+++ b/tests/unit/test_arcaflow_plugin_opensearch.py
@@ -5,7 +5,7 @@
 from opensearch_schema import (
     # Operation,
     BulkUploadObject,
-    BulkUploadOperationMeta,
+    OperationMeta,
 )
 from arcaflow_plugin_sdk import plugin
 
@@ -29,7 +29,7 @@ def test_serialization():
                             # Operation.INDEX: BulkUploadOperationMeta(
                             # Temporarily changing the key to a string in order to work
                             # around a workflow validation failure for the enum as a key
-                            "index": BulkUploadOperationMeta(
+                            "index": OperationMeta(
                                 _index="myotherindex",
                                 _id="abc123",
                             ),
@@ -44,7 +44,7 @@ def test_serialization():
                             # Operation.CREATE: BulkUploadOperationMeta(),
                             # Temporarily changing the key to a string in order to work
                             # around a workflow validation failure for the enum as a key
-                            "create": BulkUploadOperationMeta(),
+                            "create": OperationMeta(),
                         },
                         data={
                             "key1": "item 2 data value 1",