diff --git a/app/ai/client.py b/app/ai/client.py
index 6a126ab..282a7a8 100644
--- a/app/ai/client.py
+++ b/app/ai/client.py
@@ -54,14 +54,24 @@ def parse_json_response(raw: str) -> dict | None:
     # 4. greedy slice fallback — first '{' ~ last '}' 까지
     first = cleaned.find("{")
     last = cleaned.rfind("}")
-    if first >= 0 and last > first:
-        candidate = cleaned[first : last + 1]
-        try:
-            obj = json.loads(candidate)
-            return obj if isinstance(obj, dict) else None
-        except json.JSONDecodeError:
-            return None
-    return None
+    if first < 0 or last <= first:
+        return None
+    candidate = cleaned[first : last + 1]
+    try:
+        obj = json.loads(candidate)
+        return obj if isinstance(obj, dict) else None
+    except json.JSONDecodeError:
+        pass
+    # 5. (Phase 4-A 후속) Markdown 줄바꿈이 JSON string literal 안에 raw 로 들어간
+    #    케이스 방어. JSON 표준은 string 안 raw newline 금지. raw \n / \r 을 \\n/\\r 로
+    #    escape 후 재시도. 이미 escape 된 ``\\n`` (Python str 로는 backslash+n 두 글자)
+    #    는 raw newline 아니라 영향 없음.
+    escaped = candidate.replace("\r\n", "\\n").replace("\n", "\\n").replace("\r", "\\r")
+    try:
+        obj = json.loads(escaped)
+        return obj if isinstance(obj, dict) else None
+    except json.JSONDecodeError:
+        return None
 
 # 프롬프트 로딩
 PROMPTS_DIR = Path(__file__).parent.parent / "prompts"