diff --git a/scripts/validate-param.sh b/scripts/validate-param.sh
index 915809f..7fc6ab1 100755
--- a/scripts/validate-param.sh
+++ b/scripts/validate-param.sh
@@ -1,5 +1,7 @@
 #!/bin/bash
 
+set -e  # Exit immediately if a command exits with a non-zero status.
+
 # Extract inputs
 PARAMS=$PARAMS
 WORKFLOW_FILE=$WORKFLOW_FILE
@@ -35,6 +37,11 @@ echo "${PARAMS}" | jq -c 'to_entries | .[]' | while read -r step; do
 
     ACTUAL_VALUE=$(echo "${STEP_CONTENT}" | yq e ".${PARAM}" -)
 
+    if [ "${ACTUAL_VALUE}" == "null" ]; then
+      echo "The parameter ${PARAM} for step ${STEP_ID} is not set."
+      exit 1
+    fi
+
     if [ "${ACTUAL_VALUE}" != "${EXPECTED_VALUE}" ]; then
       echo "The parameter ${PARAM} for step ${STEP_ID} is not set to ${EXPECTED_VALUE}. Current value: ${ACTUAL_VALUE}"
       exit 1