diff --git a/packages/models-library/src/models_library/functions.py b/packages/models-library/src/models_library/functions.py
index 3640084a499..5e9371cd248 100644
--- a/packages/models-library/src/models_library/functions.py
+++ b/packages/models-library/src/models_library/functions.py
@@ -75,7 +75,10 @@ class FunctionClass(str, Enum):
 # see here https://github.com/ITISFoundation/osparc-simcore/issues/7659
 FunctionInputs: TypeAlias = dict[str, Any] | None
 
-FunctionInputsList: TypeAlias = list[FunctionInputs]
+FunctionInputsList: TypeAlias = Annotated[
+    list[FunctionInputs],
+    Field(max_length=50),
+]
 
 FunctionOutputs: TypeAlias = dict[str, Any] | None
 
diff --git a/services/api-server/openapi.json b/services/api-server/openapi.json
index c4ad831452d..19ee0370e76 100644
--- a/services/api-server/openapi.json
+++ b/services/api-server/openapi.json
@@ -7699,6 +7699,7 @@
                     }
                   ]
                 },
+                "maxItems": 50,
                 "title": "Function Inputs List"
               }
             }
diff --git a/tests/performance/locustfiles/functions/map_test_sleeper.py b/tests/performance/locustfiles/functions/map_test_sleeper.py
index 1e4066a951c..9c2bebbb809 100644
--- a/tests/performance/locustfiles/functions/map_test_sleeper.py
+++ b/tests/performance/locustfiles/functions/map_test_sleeper.py
@@ -3,7 +3,7 @@
 # dependencies = [
 #     "httpx",
 #     "matplotlib",
-#     "osparc>=0.8.3.post0.dev26",
+#     "osparc>0.8.3.post0.dev26",
 #     "tenacity",
 #     "tqdm",
 # ]