diff --git a/fedn/network/api/client.py b/fedn/network/api/client.py
index cd0ca5a7a..d26be03ff 100644
--- a/fedn/network/api/client.py
+++ b/fedn/network/api/client.py
@@ -571,7 +571,7 @@ def start_session(
         round_buffer_size: int = -1,
         delete_models: bool = True,
         validate: bool = True,
-        helper: str = "numpyhelper",
+        helper: str = "",
         min_clients: int = 1,
         requested_clients: int = 8,
     ):
diff --git a/fedn/network/api/interface.py b/fedn/network/api/interface.py
index 663add77e..5cd465085 100644
--- a/fedn/network/api/interface.py
+++ b/fedn/network/api/interface.py
@@ -963,7 +963,7 @@ def start_session(
         round_buffer_size=-1,
         delete_models=True,
         validate=True,
-        helper="numpyhelper",
+        helper="",
         min_clients=1,
         requested_clients=8,
     ):
@@ -1002,13 +1002,17 @@ def start_session(
             return jsonify({"success": False, "message": "A session is already running."})
 
         # Check if compute package is set
-        if not self.statestore.get_compute_package():
+        package = self.statestore.get_compute_package()
+        if not package:
             return jsonify(
                 {
                     "success": False,
                     "message": "No compute package set. Set compute package before starting session.",
                 }
             )
+        if not helper:
+            # get helper from compute package
+            helper = package["helper"]
 
         # Check that initial (seed) model is set
         if not self.statestore.get_initial_model():