diff --git a/lib/onnx/tests/print.expected b/lib/onnx/tests/print.expected
index e5444a6f08f881a2a427ccc2df25ac60c6d317cc..8088b7083d16a0d4a3c4fde8abf014b524fbd91e 100644
--- a/lib/onnx/tests/print.expected
+++ b/lib/onnx/tests/print.expected
@@ -1,4 +1,4 @@
 true
 ok
 ok
-Input name 0
+1 files checked
diff --git a/src/transformations/native_nn_prover.ml b/src/transformations/native_nn_prover.ml
index 7cd8fd9d170146231316c937201b19e139aa1b5f..3bac14153a02920ac73e6459a86f34f3deafc8ae 100644
--- a/src/transformations/native_nn_prover.ml
+++ b/src/transformations/native_nn_prover.ml
@@ -185,7 +185,8 @@ let create_new_nn env input_vars outputs : string =
   assert (
     IR.Shape.equal output.shape (IR.Shape.of_array [| List.length outputs |]));
   let nn = IR.create output in
-  let filename = Stdlib.Filename.temp_file "caisar" ".onnx" in
+  let temp_dir = Sys.getenv "CAISAR_ONNX_OUTPUT_DIR" in
+  let filename = Stdlib.Filename.temp_file ?temp_dir "caisar" ".onnx" in
   Onnx.Simple.write nn filename;
   filename
 
diff --git a/tests/acasxu.t b/tests/acasxu.t
index aaec5a866e4c2dc41b44f76587d8daaebff10957..2612b32215fad627641549147c7d0323b6f2367b 100644
--- a/tests/acasxu.t
+++ b/tests/acasxu.t
@@ -4,6 +4,9 @@ Test verify on acasxu
   $ bin/pyrat.py --version
   PyRAT 1.1
 
+  $ mkdir out
+  $ export CAISAR_ONNX_OUTPUT_DIR=out
+
   $ cat > file.mlw <<EOF
   > theory T
   >   use ieee_float.Float64
@@ -1179,3 +1182,6 @@ Test verify on acasxu
   Goal run3'vc: Unknown ()
   Goal test'vc: Unknown ()
   Goal P3: Unknown ()
+
+  $ python3 bin/inspect_onnx.py
+  12 files checked
diff --git a/tests/bin/inspect_onnx.py b/tests/bin/inspect_onnx.py
index a109a495a11f9aef38d80f41c26d4cefb9e5559f..800f144e5a7c67d8cc0caee9f508f0e691ad8b5c 100644
--- a/tests/bin/inspect_onnx.py
+++ b/tests/bin/inspect_onnx.py
@@ -1,17 +1,10 @@
 import onnx
 import os
 
-for file in os.listdir("out"):
+l = os.listdir("out")
+
+for file in l:
     m = onnx.load(os.path.join("out", file))
-    if len(m.graph.initializer) >= 1:
-        initi = m.graph.initializer[0]
-        print(
-            "Initializer name {name} has data {val:3.3f}".format(
-                name=initi.name, val=initi.float_data[2]
-            )
-        )
-    if len(m.graph.input) >= 1:
-        print(
-            f"Input name {m.graph.input[0].name}"
-        )
     onnx.checker.check_model(m)
+    
+print(len(l),"files checked")
\ No newline at end of file
diff --git a/tests/nier_to_onnx.t b/tests/nier_to_onnx.t
index e062cca4fce43f3ba877669b068b67bc7b521a47..d754d03be90f16fbd34cf57f009b89b0f61e49ed 100644
--- a/tests/nier_to_onnx.t
+++ b/tests/nier_to_onnx.t
@@ -26,4 +26,4 @@ Test verify
 Data should be 0.135
 
   $ python3 bin/inspect_onnx.py
-  Input name 0
+  1 files checked