diff --git a/schemas/config/defs.schema.json b/schemas/config/defs.schema.json
index 5c9d0cc..a0176ed 100644
--- a/schemas/config/defs.schema.json
+++ b/schemas/config/defs.schema.json
@@ -209,6 +209,10 @@
     },
     "choices": {
       "oneOf": [
+        {
+          "type": "string",
+          "description": "Allow !include string for tibi-server YAML include"
+        },
         {
           "type": "array",
           "items": {