diff --git a/kokoro/run_tests.sh b/kokoro/run_tests.sh
index 96ec3dcbc4..8b81f3f0dc 100755
--- a/kokoro/run_tests.sh
+++ b/kokoro/run_tests.sh
@@ -86,7 +86,7 @@ run_all_linux_tests() {
     run_linux_tests "python"
 
     local -a MANUAL_TOOLS_TARGETS
-    if [[ -n "{KOKORO_ROOT}" ]]; then
+    if [[ -n "${KOKORO_ROOT}" ]]; then
       MANUAL_TOOLS_TARGETS+=(
         "//testing/cc:aws_kms_aead_test"
         "//testing/cc:gcp_kms_aead_test"