diff --git a/pyinfra/file_descriptor_builder.py b/pyinfra/file_descriptor_builder.py
index 5330b06..8cf4da2 100644
--- a/pyinfra/file_descriptor_builder.py
+++ b/pyinfra/file_descriptor_builder.py
@@ -38,6 +38,26 @@ class RedFileDescriptorBuilder(FileDescriptorBuilder):
 
     def build_file_descriptor(self, queue_item_body, end="input"):
 
+        def pages():
+            # return [queue_item_body["id"]] if end == "output" else []
+            if end == "input":
+                print("?!?!?!?!?!")
+                if "id" in queue_item_body:
+                    return [queue_item_body["id"]]
+                else:
+                    # return queue_item_body["pages"]
+                    # return [] if file_pattern["subdir"] else queue_item_body["pages"]
+                    # return [] if len(queue_item_body["pages"]) > 1 else queue_item_body["pages"]
+                    # return []  # single input
+                    # return queue_item_body["pages"]  # multi input
+                    print(file_pattern)
+                    return queue_item_body["pages"] if file_pattern["multi"] else []
+            elif end == "output":
+                # return [queue_item_body["id"]] if "id" in queue_item_body else queue_item_body["pages"]
+                return [queue_item_body["id"]]
+            else:
+                raise ValueError(f"Invalid argument: {end=}")  # TODO: use an enum for `end`
+
         operation = queue_item_body.get("operation", self.default_operation_name)
 
         file_pattern = self.operation2file_patterns[operation][end]
@@ -46,7 +66,7 @@ class RedFileDescriptorBuilder(FileDescriptorBuilder):
 
         file_descriptor = {
             **project(queue_item_body, ["dossierId", "fileId", "pages"]),
-            "pages": [queue_item_body["id"]] if end == "output" else [],
+            "pages": pages(),
             "extension": file_pattern["extension"],
             "subdir": file_pattern["subdir"],
         }
diff --git a/pyinfra/file_descriptor_manager.py b/pyinfra/file_descriptor_manager.py
index 546402e..c69dfa9 100644
--- a/pyinfra/file_descriptor_manager.py
+++ b/pyinfra/file_descriptor_manager.py
@@ -46,11 +46,13 @@ class FileDescriptorManager:
         return self.get_object_descriptor(queue_item_body, end="input")
 
     def get_output_object_descriptor(self, storage_upload_info):
+        print(1111111111111111111111111111111111111111111)
         r = self.get_object_descriptor(storage_upload_info, end="output")
         print(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>", r)
         return r
 
     def get_object_descriptor(self, queue_item_body, end):
+        print(22222222222222222222222222222222222222222, end, queue_item_body)
         # TODO: this is complected with the Storage class API
         # FIXME: bad coupling
         return {
diff --git a/pyinfra/visitor/downloader.py b/pyinfra/visitor/downloader.py
index 725b7c2..0324f1c 100644
--- a/pyinfra/visitor/downloader.py
+++ b/pyinfra/visitor/downloader.py
@@ -51,7 +51,10 @@ class Downloader:
         yield from self.storage.get_all_object_names(self.bucket_name, prefix=prefix)
 
     def get_pattern_filter(self, queue_item_body):
+        print("<<<<<<<<<<<<<<<<<<<<<<<<<<<", queue_item_body)
         file_pattern = self.file_descriptor_manager.build_input_matcher(queue_item_body)
+        print(f"{file_pattern=}")
+        # input()
         logger.debug(f"Filtering pattern: {file_pattern if len(file_pattern) <= 120 else (file_pattern[:120]+'...')}")
         matches_pattern = flift(file_pattern)
         return matches_pattern
diff --git a/test/config.yaml b/test/config.yaml
index 5b17f66..bf22b6d 100644
--- a/test/config.yaml
+++ b/test/config.yaml
@@ -1,17 +1,11 @@
 service:
   response_formatter: identity
   operations:
-#    multi_inp_op:
-#      input:
-#        subdir: op_inp_files
-#        extension: IN.gz
-#      output:
-#        subdir: op_outp_files
-#        extension: OUT.gz
     upper:
       input:
         subdir: ""
         extension: up_in.gz
+        multi: False
       output:
         subdir: ""
         extension: up_out.gz
@@ -19,6 +13,7 @@ service:
       input:
         subdir: ""
         extension: extr_in.gz
+        multi: False
       output:
         subdir: "extractions"
         extension: gz
@@ -26,6 +21,7 @@ service:
       input:
         subdir: ""
         extension: rot_in.gz
+        multi: False
       output:
         subdir: ""
         extension: rot_out.gz
@@ -33,6 +29,7 @@ service:
       input:
         subdir: ""
         extension: cls_in.gz
+        multi: True
       output:
         subdir: ""
         extension: cls_out.gz
@@ -40,15 +37,15 @@ service:
       input:
         subdir: ""
         extension: pgs_in.gz
+        multi: False
       output:
         subdir: "pages"
         extension: pgs_out.gz
-
-
     default:
       input:
         subdir: ""
         extension: IN.gz
+        multi: False
       output:
         subdir: ""
         extension: OUT.gz
@@ -79,4 +76,4 @@ webserver:
 mock_analysis_endpoint: "http://127.0.0.1:5000"
 
 use_docker_fixture: 0
-logging: 1
\ No newline at end of file
+logging: 0
\ No newline at end of file
diff --git a/test/conftest.py b/test/conftest.py
index d10b12c..b5aa614 100644
--- a/test/conftest.py
+++ b/test/conftest.py
@@ -89,8 +89,8 @@ def mock_make_load_data():
     return load_data
 
 
-def pytest_make_parametrize_id(config, val, argname):
-    return f"\n\t{argname}={val}\n"
+# def pytest_make_parametrize_id(config, val, argname):
+#     return f"\n\t{argname}={val}\n"
 
 
 @pytest.fixture
diff --git a/test/fixtures/server.py b/test/fixtures/server.py
index dcc428f..4e78829 100644
--- a/test/fixtures/server.py
+++ b/test/fixtures/server.py
@@ -102,7 +102,7 @@ def server_side_test(request):
 
 
 @pytest.fixture
-def core_operation(item_type, one_to_many, analysis_task):
+def core_operation(many_to_n, item_type, one_to_many, analysis_task):
     def duplicate(string: bytes, metadata):
         for _ in range(2):
             yield upper(string, metadata), metadata
@@ -117,7 +117,9 @@ def core_operation(item_type, one_to_many, analysis_task):
     def extract(string: bytes, metadata):
         print("extract>>>>>>>>>>>", metadata)
         print(string.decode())
-        for i, c in project(dict(enumerate(string.decode())), metadata.get("pages", range(len(string.decode())))).items():
+        for i, c in project(
+            dict(enumerate(string.decode())), metadata.get("pages", range(len(string.decode())))
+        ).items():
             metadata["id"] = i
             print(i)
             yield c.encode(), metadata
@@ -136,18 +138,34 @@ def core_operation(item_type, one_to_many, analysis_task):
             yield f"page_{i}".encode(), metadata
 
     params2op = {
-        False: {
-            "string": {False: upper},
-            "image": {False: rotate, True: classify},
-        },
         True: {
-            "string": {False: extract},
-            "pdf": {False: stream_pages},
+            True: {},
+            False: {
+                "image": {True: classify},
+            },
         },
+        False: {
+            True: {
+                "string": {False: extract},
+                "pdf": {False: stream_pages},
+            },
+            False: {
+                "string": {False: upper},
+                "image": {False: rotate},
+            },
+        },
+            # False: {
+            #     "string": {False: upper},
+            #     "image": {False: rotate, True: classify},
+            # },
+            # True: {
+            #     "string": {False: extract},
+            #     "pdf": {False: stream_pages},
+            # },
     }
 
     try:
-        return params2op[one_to_many][item_type][analysis_task]
+        return params2op[many_to_n][one_to_many][item_type][analysis_task]
     except KeyError:
         msg = f"No operation defined for [{one_to_many=}, {item_type=}, {analysis_task=}]."
         pytest.skip(msg)
diff --git a/test/integration_tests/serve_test.py b/test/integration_tests/serve_test.py
index 5d5b63b..c89553f 100644
--- a/test/integration_tests/serve_test.py
+++ b/test/integration_tests/serve_test.py
@@ -78,7 +78,7 @@ from test.config import CONFIG as TEST_CONFIG
 @pytest.mark.parametrize(
     "many_to_n",
     [
-        # True,
+        True,
         False,
     ],
 )
@@ -157,8 +157,9 @@ def upload_data_to_folder_in_storage_and_publish_single_request_to_queue(
 
     for data, page in zip(map(first, data_message_pairs), pages):
         object_descriptor = file_descriptor_manager.get_input_object_descriptor({**ref_message, "id": page})
-        object_descriptor["object_name"] = build_filepath(object_descriptor, page)
         print(f"{object_descriptor=}")
+        object_descriptor["object_name"] = build_filepath(object_descriptor, page)
+        # input()
 
         storage.put_object(**object_descriptor, data=compress(data))
 
@@ -170,6 +171,7 @@ def build_filepath(object_descriptor, page):
     parts = object_name.split("/")
     path = "/".join(parts)
     path = re.sub(r"id:\d", f"id:{page}", path)
+    print(path)
 
     return path