diff --git a/bin/compose-core b/bin/compose-core
index b4f236e..6bf953a 100755
--- a/bin/compose-core
+++ b/bin/compose-core
@@ -2477,7 +2477,7 @@ get_all_relations () {
                     return 1
                     ;;
             esac
-            constraint=$(echo "$relation_def" | shyaml get-value constraint auto-pair 2>/dev/null)
+            constraint=$(echo "$relation_def" | shyaml get-value constraint optional 2>/dev/null)
             case "$constraint" in
                 "required")
                     required+=("$service" "$relation_name" "$relation_def")