diff --git a/src/openeo_aggregator/backend.py b/src/openeo_aggregator/backend.py
index afc35092..3ad51839 100644
--- a/src/openeo_aggregator/backend.py
+++ b/src/openeo_aggregator/backend.py
@@ -677,8 +677,6 @@ def _get_connection_and_backend_service_id(
 
     def service_types(self) -> dict:
         """https://openeo.org/documentation/1.0/developers/api/reference.html#operation/list-service-types"""
-        # TODO: implement household data to cache useful data for selecting backend based on service and backend's capabilities.
-
         cached_info = self._memoizer.get_or_call(key=("_get_service_types",), callback=self._get_service_types)
         # Convert the cached results back to the format that service_types should return.
         return {name: data["service_type"] for name, data, in cached_info.items()}
@@ -689,21 +687,21 @@ def _find_backend_id_for_service_type(self, service_type: str) -> Optional[str]:
         return cached_info.get(service_type, {}).get("backend_id")
 
     def _get_service_types(self) -> dict:
-        """Returns a dict that maps the service name to a dict that contains 2 items:
+        """Returns a dict that maps the service name to another dict that contains 2 items:
         1) the backend_id that provides this secondary service
         2) the service_types for self.service_types.
 
         For example:
         {'WMTS':
-	        {'backend_id': 'b1',
-	         'service_type':   // contains what backend b1 returned for service type WMTS.
+            {'backend_id': 'b1',
+             'service_type':   // contains what backend b1 returned for service type WMTS.
                 {'configuration':
                     ...
                 }
             }
          'WMS':
             {'backend_id': 'b2',
-	         'service_type':
+             'service_type':
                 {'configuration':
                     ...
                 }
@@ -724,6 +722,8 @@ def _get_service_types(self) -> dict:
             https://github.com/Open-EO/openeo-aggregator/issues/83
             https://github.com/Open-EO/openeo-aggregator/issues/84
         """
+
+        # TODO: Issue #85 data about backend capabilities could be added to the service_types data structure as well.
         service_types = {}
 
         # TODO: Instead of merge: prefix each type with backend-id? #83
@@ -799,6 +799,9 @@ def create_service(self, user_id: str, process_graph: dict, service_type: str, a
         """
         # TODO: configuration is not used. What to do with it?
 
+        # TODO: Strictly speaking it would be better to override _create_service instead of create_service
+        #       but for now we override create_service so we can keep the special case for the "sentinelhub" backend.
+
         # TODO: hardcoded/forced "SentinelHub only" support for now.
         #       Instead, properly determine backend based on service type?
         #       See https://github.com/Open-EO/openeo-aggregator/issues/78#issuecomment-1326180557
diff --git a/tests/test_backend.py b/tests/test_backend.py
index 94f0f3d2..d948e06d 100644
--- a/tests/test_backend.py
+++ b/tests/test_backend.py
@@ -371,14 +371,15 @@ def test_create_service_raises_serviceunsupportedexception(
     ):
         """When it gets a request for a service type that no backend supports, it raises ServiceUnsupportedException."""
 
-        # Set up one service type. Don't want test to succeed because there are no services at all.
+        # At least 1 service type must be present.
+        # We don't want test to succeed erroneously simply because there are no services at all.
         requests_mock.get(backend1 + "/service_types", json=self.SERVICE_TYPES_ONLT_WMTS)
 
         non_existent_service_id =  "b1-doesnotexist"
-        # check that this requests_mock does not get called
+        # Check that this requests_mock does not get called.
         location_backend_1 = backend1 + "/services/" + non_existent_service_id
         process_graph = {"foo": {"process_id": "foo", "arguments": {}}}
-        requests_mock.post(
+        mock_post = requests_mock.post(
             backend1 + "/services",
             headers={
                 "OpenEO-Identifier": "wmts-foo",
@@ -398,6 +399,7 @@ def test_create_service_raises_serviceunsupportedexception(
                     api_version="1.0.0",
                     configuration={}
                 )
+            assert not mock_post.called
 
 
     @pytest.mark.parametrize("exception_class", [OpenEoApiError, OpenEoRestError])