diff --git a/pkg/config/compatibility.go b/pkg/config/compatibility.go
index 2048333782..cb88e3ba31 100644
--- a/pkg/config/compatibility.go
+++ b/pkg/config/compatibility.go
@@ -151,6 +151,11 @@ func cudaVersionFromTorchPlusVersion(ver string) (string, string) {
 }
 
 func cudasFromTorch(ver string) ([]string, error) {
+	if ver == "" {
+		return nil, fmt.Errorf(
+			"torch version must be specified when using CUDA",
+		)
+	}
 	cudas := []string{}
 
 	// Check the version modifier on torch (such as +cu118)
diff --git a/python/cog/types.py b/python/cog/types.py
index cc240a0647..0c01680569 100644
--- a/python/cog/types.py
+++ b/python/cog/types.py
@@ -380,7 +380,14 @@ def __wrapped__(self) -> Any:
         except AttributeError:
             pass
         url = object.__getattribute__(self, "__url__")
-        resp = requests.get(url, stream=True, timeout=10)
+
+        headers = {}
+        ua = os.getenv("COG_USER_AGENT")
+        if ua:
+            headers["User-Agent"] = ua
+
+        resp = requests.get(url, stream=True, timeout=10,headers=headers)
+        
         resp.raise_for_status()
         resp.raw.decode_content = True
         object.__setattr__(self, "__target__", resp.raw)