diff --git a/tasks/check-stemcell-versions/main.go b/tasks/check-stemcell-versions/main.go
index d64ca5b8..ce190337 100644
--- a/tasks/check-stemcell-versions/main.go
+++ b/tasks/check-stemcell-versions/main.go
@@ -9,8 +9,12 @@ import (
 )
 
 func main() {
+	if len(os.Args) < 3 {
+		log.Fatalf("Usage: %s <buildDir> <branchToCompare>", os.Args[0])
+	}
+
 	buildDir := os.Args[1]
-	branchToCompare := os.Getenv("BRANCH_TO_COMPARE")
+	branchToCompare := os.Args[2]
 
 	content, err := os.ReadFile(filepath.Join(buildDir, "cf-deployment-main", "cf-deployment.yml"))
 	if err != nil {
diff --git a/tasks/check-stemcell-versions/task b/tasks/check-stemcell-versions/task
index 35ba3aee..ca4da160 100755
--- a/tasks/check-stemcell-versions/task
+++ b/tasks/check-stemcell-versions/task
@@ -3,9 +3,10 @@ set -eu
 
 function main() {
   root_dir="$PWD"
-  : "${BRANCH_TO_COMPARE:=release-candidate}"
+  branch_to_compare="${BRANCH_TO_COMPARE:-release-candidate}"
+
   pushd "$(dirname $0)"
-    BRANCH_TO_COMPARE=$BRANCH_TO_COMPARE  go run main.go "${root_dir}"
+    go run main.go "${root_dir}" "${branch_to_compare}"
   popd
 }