diff --git a/nixos/tests/exercise-storage.py b/nixos/tests/exercise-storage.py
index e3a1d4d2ec7674042487cc0c6dabc670fcd6561d..288a846d87e6fc468f22bc0e634ae4430c17791b 100755
--- a/nixos/tests/exercise-storage.py
+++ b/nixos/tests/exercise-storage.py
@@ -85,10 +85,13 @@ def get_api_root(path):
         return hyperlink.URL.from_text(f.read().strip())
 
 def tahoe_put(api_root, data, **kwargs):
+    uri = api_root.child(u"uri").to_uri()
     response = requests.put(
-        api_root.child(u"uri").to_uri(),
+        uri,
         BytesIO(data),
+        headers={"accept": "text/plain"},
     )
+    print(f"PUT {uri} responded:\n{response.text}\n")
     response.raise_for_status()
     return response.text