diff --git a/src/ref.js b/src/ref.js
index 0575216..5741c90 100644
--- a/src/ref.js
+++ b/src/ref.js
@@ -2,6 +2,7 @@
 //     https://github.com/OAI/OpenAPI-Specification/tree/master/versions
 
 const FIELD_PATTERN = "([a-zA-Z0-9\\-_]|[^\x01-\x7E\uFF61-\uFF9F])+";
+const MAX_JSON_PATH_DEPTH = 100;
 
 const REF_TYPES = {
   parameters: (path) => {
@@ -68,7 +69,10 @@ function getRefType(path) {
       return k;
     }
   }
-  console.log(`unknown component type at "${path}". fallback to include.`);
+  console.warn(`could not infer $ref type at "${path}". fallback to include.`);
+  if (path.split(".").length > MAX_JSON_PATH_DEPTH) {
+    throw new Error(`JSON path depth exceeds ${MAX_JSON_PATH_DEPTH}, aborting...`);
+  }
   return "unknown";
 }