diff --git a/backend/app/api/routes/chat.py b/backend/app/api/routes/chat.py
index f200b95..e6e3e9b 100644
--- a/backend/app/api/routes/chat.py
+++ b/backend/app/api/routes/chat.py
@@ -6,7 +6,7 @@
 from pydantic import BaseModel, Field
 from sse_starlette.sse import EventSourceResponse
 
-from app.services.llm import get_english_translation, get_response_stream_async
+from app.services.llm import get_english_translation, get_response_stream_async, generate_chat_title_async
 from app.services.embedding import embedding_service
 from app.services.database import get_client
 from app.core.rate_limit import limiter
@@ -14,6 +14,8 @@
 router = APIRouter()
 logger = logging.getLogger(__name__)
 
+DEFAULT_CHAT_TITLE = "새로운 대화"
+
 class HistoryMessage(BaseModel):
     role: str
     content: str
@@ -22,6 +24,9 @@ class ChatRequest(BaseModel):
     query: str
     history: List[HistoryMessage] = Field(default_factory=list)
 
+class TitleRequest(BaseModel):
+    query: str = Field(..., max_length=1024)
+
 def _search_documents(query_vector):
     return get_client().rpc(
         'match_documents', 
@@ -127,3 +132,31 @@ async def chat_endpoint(request: Request, chat_request: ChatRequest):
     Endpoint for accepting chat queries and returning a text/event-stream response.
     """
     return EventSourceResponse(generate_chat_events(request, chat_request.query, chat_request.history))
+
+@router.post("/title")
+@limiter.limit("5/minute")
+async def chat_title_endpoint(request: Request, title_request: TitleRequest):
+    """
+    Endpoint for generating a short chat room title based on the first user query.
+    """
+    query = title_request.query.strip()
+    if not query:
+        return {"title": DEFAULT_CHAT_TITLE}
+
+    try:
+        title = await asyncio.wait_for(generate_chat_title_async(query), timeout=10.0)
+        # Handle case where LLM returns something too long or with quotes
+        title = title.replace('"', '').replace("'", "").strip()
+        if not title:
+            return {"title": DEFAULT_CHAT_TITLE}
+        MAX_TITLE_LEN = 20
+        ELLIPSIS = "..."
+        if len(title) > MAX_TITLE_LEN:
+            title = title[: MAX_TITLE_LEN - len(ELLIPSIS)] + ELLIPSIS
+        return {"title": title}
+    except asyncio.TimeoutError:
+        logger.warning("Timeout generating chat title")
+        return {"title": DEFAULT_CHAT_TITLE}
+    except Exception:
+        logger.exception("Failed to generate chat title")
+        return {"title": DEFAULT_CHAT_TITLE}
diff --git a/backend/app/services/llm.py b/backend/app/services/llm.py
index c6183b2..6682f21 100644
--- a/backend/app/services/llm.py
+++ b/backend/app/services/llm.py
@@ -120,3 +120,19 @@ async def get_response_stream_async(context: str, query: str, history: str = "")
     chain = prompt | get_llm() | StrOutputParser()
     async for chunk in chain.astream({"context": context, "chat_history": history, "query": query}):
         yield chunk
+
+title_prompt = PromptTemplate.from_template(
+    """주어진 질문을 기반으로 철학적인 대화방 제목을 15자 이내로 지어줘.
+    부연 설명 없이 제목만 출력해.
+    
+    질문: {query}
+    제목: """
+)
+
+async def generate_chat_title_async(query: str) -> str:
+    """
+    Generates a short chat title based on the user's first query using Gemini.
+    """
+    chain = title_prompt | get_llm() | StrOutputParser()
+    title = await chain.ainvoke({"query": query})
+    return title.strip()
diff --git a/backend/data/books_mapping.json b/backend/data/books_mapping.json
index 7bd9fc8..05afbfc 100644
--- a/backend/data/books_mapping.json
+++ b/backend/data/books_mapping.json
@@ -17,7 +17,7 @@
         "translated_author": "데이비드 흄",
         "aladin_data": {
             "title": "인간이란 무엇인가 - 오성 정념 도덕 본성론",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=4359030&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=4359030&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/435/90/coversum/8949705206_1.jpg",
             "author": "데이비드 흄 (지은이), 김성숙 (옮긴이)",
             "isbn": "9788949705200"
@@ -29,7 +29,7 @@
         "translated_author": "메리 울스턴크래프트",
         "aladin_data": {
             "title": "여권의 옹호",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=45690064&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=45690064&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/4569/0/coversum/8994054596_1.jpg",
             "author": "메리 울스턴크래프트 (지은이), 손영미 (옮긴이)",
             "isbn": "9788994054599"
@@ -41,7 +41,7 @@
         "translated_author": "프리드리히 니체",
         "aladin_data": {
             "title": "차라투스트라는 이렇게 말했다",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=454014&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=454014&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/45/40/coversum/s352934786_1.jpg",
             "author": "프리드리히 니체 (지은이), 장희창 (옮긴이)",
             "isbn": "9788937460944"
@@ -59,7 +59,7 @@
         "translated_author": "존 로크",
         "aladin_data": {
             "title": "존 로크의 인간 오성론 읽기",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=90592125&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=90592125&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/9059/21/coversum/k092535101_1.jpg",
             "author": "안병웅 (지은이)",
             "isbn": "9791185136318"
@@ -71,7 +71,7 @@
         "translated_author": "플라톤",
         "aladin_data": {
             "title": "소크라테스의 변명 - 크리톤 파이돈 향연, 문예교양선서 30",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=224035&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=224035&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/22/40/coversum/8931003714_3.jpg",
             "author": "플라톤 (지은이), 황문수 (옮긴이)",
             "isbn": "9788931003710"
@@ -83,7 +83,7 @@
         "translated_author": "플라톤",
         "aladin_data": {
             "title": "소크라테스의 변명·크리톤·파이돈·향연 (그리스어 원전 완역본) - 플라톤의 대화편",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=216792703&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=216792703&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/21679/27/coversum/k252636705_1.jpg",
             "author": "플라톤 (지은이), 박문재 (옮긴이)",
             "isbn": "9791190398039"
@@ -95,7 +95,7 @@
         "translated_author": "제임스 앨런",
         "aladin_data": {
             "title": "제임스 앨런 원인과 결과의 법칙 - 사람은 생각하는 대로 살게 된다",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=345588057&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=345588057&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/34558/80/coversum/k732933167_1.jpg",
             "author": "제임스 알렌 (지은이), 박선영 (옮긴이)",
             "isbn": "9791171177660"
@@ -113,7 +113,7 @@
         "translated_author": "프리드리히 니체",
         "aladin_data": {
             "title": "선악의 저편",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=174923171&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=174923171&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/17492/31/coversum/8957336117_1.jpg",
             "author": "프리드리히 니체 (지은이), 박찬국 (옮긴이)",
             "isbn": "9788957336113"
@@ -125,7 +125,7 @@
         "translated_author": "마르쿠스 툴리우스 키케로",
         "aladin_data": {
             "title": "투스쿨룸 대화",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=286336783&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=286336783&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/28633/67/coversum/8957337679_1.jpg",
             "author": "마르쿠스 툴리우스 키케로 (지은이), 김남우 (옮긴이)",
             "isbn": "9788957337677"
@@ -137,7 +137,7 @@
         "translated_author": "마르쿠스 툴리우스 키케로",
         "aladin_data": {
             "title": "키케로의 의무론 - 그의 아들에게 보낸 편지",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=852420&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=852420&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/85/24/coversum/8930606245_1.jpg",
             "author": "마르쿠스 툴리우스 키케로 (지은이), 허승일 (옮긴이)",
             "isbn": "9788930606240"
@@ -149,7 +149,7 @@
         "translated_author": "존 듀이",
         "aladin_data": {
             "title": "민주주의와 교육",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=922961&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=922961&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/92/29/coversum/8925400669_2.jpg",
             "author": "존 듀이 (지은이), 이홍우 (옮긴이)",
             "isbn": "9788925400662"
@@ -173,7 +173,7 @@
         "translated_author": "르네 데카르트",
         "aladin_data": {
             "title": "방법서설 - 이성을 잘 인도하고 학문에서 진리를 찾기 위한",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=347983217&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=347983217&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/34798/32/coversum/k152933225_1.jpg",
             "author": "르네 데카르트 (지은이), 이재훈 (옮긴이)",
             "isbn": "9791170872443"
@@ -185,7 +185,7 @@
         "translated_author": "프리드리히 니체",
         "aladin_data": {
             "title": "이 사람을 보라",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=302356844&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=302356844&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/30235/68/coversum/8957338195_1.jpg",
             "author": "프리드리히 니체 (지은이), 박찬국 (옮긴이)",
             "isbn": "9788957338193"
@@ -197,7 +197,7 @@
         "translated_author": "랠프 월도 에머슨",
         "aladin_data": {
             "title": "에머슨 수상록",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=100408&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=100408&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/10/4/coversum/8972432954_2.jpg",
             "author": "랄프 왈도 에머슨 (지은이)",
             "isbn": "9788972432951"
@@ -209,7 +209,7 @@
         "translated_author": "아르투어 쇼펜하우어",
         "aladin_data": {
             "title": "쇼펜하우어의 행복론과 인생론",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=308665960&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=308665960&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/30866/59/coversum/8932440093_1.jpg",
             "author": "아르투어 쇼펜하우어 (지은이), 홍성광 (옮긴이)",
             "isbn": "9788932440095"
@@ -221,7 +221,7 @@
         "translated_author": "베네딕투스 데 스피노자",
         "aladin_data": {
             "title": "에티카 - 개정판",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=993377&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=993377&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/99/33/coversum/8930625460_2.jpg",
             "author": "베네딕투스 데 스피노자 (지은이), 강영계 (옮긴이)",
             "isbn": "9788930625463"
@@ -239,7 +239,7 @@
         "translated_author": "플라톤",
         "aladin_data": {
             "title": "에우튀프론",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=272171162&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=272171162&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/27217/11/coversum/8957337342_1.jpg",
             "author": "플라톤 (지은이), 강성훈 (옮긴이)",
             "isbn": "9788957337349"
@@ -251,7 +251,7 @@
         "translated_author": "임마누엘 칸트",
         "aladin_data": {
             "title": "윤리형이상학 정초 - 개정2판",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=168355651&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=168355651&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/16835/56/coversum/8957336036_1.jpg",
             "author": "임마누엘 칸트 (지은이), 백종현 (옮긴이)",
             "isbn": "9788957336038"
@@ -269,7 +269,7 @@
         "translated_author": "플라톤",
         "aladin_data": {
             "title": "고르기아스",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=265344583&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=265344583&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/26534/45/coversum/8957337210_1.jpg",
             "author": "플라톤 (지은이), 김인곤 (옮긴이)",
             "isbn": "9788957337219"
@@ -287,7 +287,7 @@
         "translated_author": "프리드리히 니체",
         "aladin_data": {
             "title": "인간적인 너무나 인간적인 1",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=279599&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=279599&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/27/95/coversum/8970132619_3.jpg",
             "author": "프리드리히 니체 (지은이), 김미기 (옮긴이)",
             "isbn": "9788970132617"
@@ -305,7 +305,7 @@
         "translated_author": "플라톤",
         "aladin_data": {
             "title": "플라톤의 법률",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=4646467&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=4646467&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/464/64/coversum/8930606296_1.jpg",
             "author": "플라톤 (지은이), 박종현 (옮긴이)",
             "isbn": "9788930606295"
@@ -317,7 +317,7 @@
         "translated_author": "토마스 홉스",
         "aladin_data": {
             "title": "리바이어던 1 - 교회국가 및 시민국가의 재료와 형태 및 권력",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=2480851&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=2480851&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/248/8/coversum/s392037901_2.jpg",
             "author": "토마스 홉스 (지은이), 진석용 (옮긴이)",
             "isbn": "9788930083379"
@@ -329,7 +329,7 @@
         "translated_author": "마르쿠스 아우렐리우스",
         "aladin_data": {
             "title": "명상록 - 삶과 죽음을 고뇌한 어느 철학자 황제의 가장 사적인 기록",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=384592083&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=384592083&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/38459/20/coversum/k062135812_1.jpg",
             "author": "마르쿠스 아우렐리우스 (지은이), 정미화 (옮긴이), 그레고리 헤이스 (해제)",
             "isbn": "9791168273993"
@@ -341,7 +341,7 @@
         "translated_author": "랄프 왈도 에머슨",
         "aladin_data": {
             "title": "랄프 왈도 에머슨 : 자연",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=39251790&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=39251790&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/3925/17/coversum/8956607648_1.jpg",
             "author": "랄프 왈도 에머슨 (지은이), 서동석 (옮긴이)",
             "isbn": "9788956607641"
@@ -353,7 +353,7 @@
         "translated_author": "토마스 칼라일",
         "aladin_data": {
             "title": "영웅숭배론",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=313531822&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=313531822&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/31353/18/coversum/8935678147_1.jpg",
             "author": "토머스 칼라일 (지은이), 박상익 (옮긴이)",
             "isbn": "9788935678143"
@@ -365,7 +365,7 @@
         "translated_author": "존 스튜어트 밀",
         "aladin_data": {
             "title": "초판본 자유론 - 1859년 오리지널 초판본 표지 디자인",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=381938135&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=381938135&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/38193/81/coversum/k302034718_1.jpg",
             "author": "존 스튜어트 밀 (지은이), 김희상 (옮긴이)",
             "isbn": "9791175241961"
@@ -377,7 +377,7 @@
         "translated_author": "헨리 데이비드 소로",
         "aladin_data": {
             "title": "월든·시민 불복종 (합본 완역본)",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=284194464&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=284194464&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/28419/44/coversum/k742835213_1.jpg",
             "author": "헨리 데이비드 소로 (지은이), 이종인 (옮긴이), 허버트 웬델 글리슨 (사진)",
             "isbn": "9791139700503"
@@ -389,7 +389,7 @@
         "translated_author": "루크레티우스",
         "aladin_data": {
             "title": "사물의 본성에 관하여",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=14599483&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=14599483&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/1459/94/coversum/8957332227_1.jpg",
             "author": "루크레티우스 (지은이), 강대진 (옮긴이)",
             "isbn": "9788957332221"
@@ -401,7 +401,7 @@
         "translated_author": "카를 폰 클라우제비츠",
         "aladin_data": {
             "title": "전쟁론 - 전면완역개정판",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=86524117&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=86524117&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/8652/41/coversum/8961951424_1.jpg",
             "author": "카알 폰 클라우제비츠 (지은이), 김만수 (옮긴이)",
             "isbn": "9788961951425"
@@ -413,7 +413,7 @@
         "translated_author": "블레즈 파스칼",
         "aladin_data": {
             "title": "파스칼의 팡세",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=367576319&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=367576319&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/36757/63/coversum/k952030294_1.jpg",
             "author": "블레즈 파스칼 (지은이), 강현규 (엮은이), 이선미 (옮긴이)",
             "isbn": "9791160029529"
@@ -425,7 +425,7 @@
         "translated_author": "임마누엘 칸트",
         "aladin_data": {
             "title": "영구 평화론 - 하나의 철학적 기획, 개정판",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=2881780&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=2881780&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/288/17/coversum/8930610439_1.jpg",
             "author": "임마누엘 칸트 (지은이), 이한구 (옮긴이)",
             "isbn": "9788930610438"
@@ -437,7 +437,7 @@
         "translated_author": "플라톤",
         "aladin_data": {
             "title": "소크라테스의 변명·크리톤·파이돈·향연 (그리스어 원전 완역본) - 플라톤의 대화편",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=216792703&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=216792703&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/21679/27/coversum/k252636705_1.jpg",
             "author": "플라톤 (지은이), 박문재 (옮긴이)",
             "isbn": "9791190398039"
@@ -449,7 +449,7 @@
         "translated_author": "플라톤",
         "aladin_data": {
             "title": "파이드로스 - 그리스어 원전 번역판",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=1820615&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=1820615&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/182/6/coversum/8931005881_2.jpg",
             "author": "플라톤 (지은이), 조대호 (옮긴이)",
             "isbn": "9788931005882"
@@ -467,7 +467,7 @@
         "translated_author": "플루타르코스",
         "aladin_data": {
             "title": "플루타르코스 영웅전",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=6970308&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=6970308&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/697/3/coversum/8991290337_2.jpg",
             "author": "플루타르코스 (지은이), 천병희 (옮긴이)",
             "isbn": "9788991290334"
@@ -479,7 +479,7 @@
         "translated_author": "아리스토텔레스",
         "aladin_data": {
             "title": "정치학",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=4399813&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=4399813&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/439/98/coversum/8991290280_1.jpg",
             "author": "아리스토텔레스 (지은이), 천병희 (옮긴이)",
             "isbn": "9788991290280"
@@ -503,7 +503,7 @@
         "translated_author": "카를 구스타프 융",
         "aladin_data": {
             "title": "칼 융 무의식의 심리학",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=300205010&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=300205010&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/30020/50/coversum/k222838355_1.jpg",
             "author": "칼 구스타프 융 (지은이), 정명진 (옮긴이)",
             "isbn": "9791159201479"
@@ -533,7 +533,7 @@
         "translated_author": "존 로크",
         "aladin_data": {
             "title": "통치론 - 시민정부의 참된 기원, 범위 및 그 목적에 관한 시론",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=301106377&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=301106377&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/30110/63/coversum/897291780x_1.jpg",
             "author": "존 로크 (지은이), 강정인, 문지영 (옮긴이)",
             "isbn": "9788972917809"
@@ -545,7 +545,7 @@
         "translated_author": "헤르만 헤세",
         "aladin_data": {
             "title": "싯다르타",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=329596&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=329596&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/32/95/coversum/s062934786_1.jpg",
             "author": "헤르만 헤세 (지은이), 박병덕 (옮긴이)",
             "isbn": "9788937460586"
@@ -557,7 +557,7 @@
         "translated_author": "손무",
         "aladin_data": {
             "title": "손자병법 - 이겨놓고 싸우는 인생의 지혜",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=372980631&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=372980631&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/37298/6/coversum/k292031545_1.jpg",
             "author": "손무 (지은이), 소준섭 (옮긴이)",
             "isbn": "9791139728002"
@@ -569,7 +569,7 @@
         "translated_author": "플라톤",
         "aladin_data": {
             "title": "소크라테스의 변명·크리톤·파이돈·향연 (그리스어 원전 완역본) - 플라톤의 대화편",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=216792703&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=216792703&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/21679/27/coversum/k252636705_1.jpg",
             "author": "플라톤 (지은이), 박문재 (옮긴이)",
             "isbn": "9791190398039"
@@ -587,7 +587,7 @@
         "translated_author": "프리드리히 빌헬름 니체",
         "aladin_data": {
             "title": "안티크리스트",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=35425033&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=35425033&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/3542/50/coversum/8957333444_1.jpg",
             "author": "프리드리히 니체 (지은이), 박찬국 (옮긴이)",
             "isbn": "9788957333440"
@@ -599,7 +599,7 @@
         "translated_author": "프리드리히 빌헬름 니체",
         "aladin_data": {
             "title": "비극의 탄생",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=988511&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=988511&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/98/85/coversum/8957331077_1.jpg",
             "author": "프리드리히 니체 (지은이), 박찬국 (옮긴이)",
             "isbn": "9788957331071"
@@ -611,7 +611,7 @@
         "translated_author": "프리드리히 니체",
         "aladin_data": {
             "title": "우상의 황혼",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=64193963&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=64193963&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/6419/39/coversum/8957334513_1.jpg",
             "author": "프리드리히 니체 (지은이), 박찬국 (옮긴이)",
             "isbn": "9788957334515"
@@ -635,7 +635,7 @@
         "translated_author": "카를 마르크스, 프리드리히 엥겔스",
         "aladin_data": {
             "title": "공산당 선언",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=143257420&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=143257420&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/14325/74/coversum/k172532941_1.jpg",
             "author": "카를 마르크스, 프리드리히 엥겔스 (지은이), 심철민 (옮긴이)",
             "isbn": "9791187036548"
@@ -653,7 +653,7 @@
         "translated_author": "보에티우스",
         "aladin_data": {
             "title": "철학의 위안 - 완역본",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=147121964&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=147121964&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/14712/19/coversum/k002532053_2.jpg",
             "author": "아니키우스 보이티우스 (지은이), 박문재 (옮긴이)",
             "isbn": "9791187142430"
@@ -665,7 +665,7 @@
         "translated_author": "이마누엘 칸트",
         "aladin_data": {
             "title": "순수이성비판 1",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=669748&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=669748&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/66/97/coversum/8957330836_1.jpg",
             "author": "임마누엘 칸트 (지은이), 백종현 (옮긴이)",
             "isbn": "9788957330838"
@@ -677,7 +677,7 @@
         "translated_author": "에픽테토스",
         "aladin_data": {
             "title": "[POD] 에픽테토스 편람 (스토아 사상 철학자) : The Enchiridion (영어원서)",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=231320657&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=231320657&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/23132/6/coversum/k022637708_1.jpg",
             "author": "에픽테토스 (지은이)",
             "isbn": "9791127295479"
@@ -695,7 +695,7 @@
         "translated_author": "아르투어 쇼펜하우어",
         "aladin_data": {
             "title": "쇼펜하우어의 행복론과 인생론",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=308665960&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=308665960&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/30866/59/coversum/8932440093_1.jpg",
             "author": "아르투어 쇼펜하우어 (지은이), 홍성광 (옮긴이)",
             "isbn": "9788932440095"
@@ -707,7 +707,7 @@
         "translated_author": "아리스토텔레스",
         "aladin_data": {
             "title": "니코마코스 윤리학 - 그리스어 원전 번역, 개정판",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=31685631&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=31685631&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/3168/56/coversum/8991290523_3.jpg",
             "author": "아리스토텔레스 (지은이), 천병희 (옮긴이)",
             "isbn": "9788991290525"
@@ -719,7 +719,7 @@
         "translated_author": "프리드리히 니체",
         "aladin_data": {
             "title": "도덕의 계보",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=274647853&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=274647853&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/27464/78/coversum/8957337350_1.jpg",
             "author": "프리드리히 니체 (지은이), 박찬국 (옮긴이)",
             "isbn": "9788957337356"
@@ -761,7 +761,7 @@
         "translated_author": "윌리엄 블레이크",
         "aladin_data": {
             "title": "천국과 지옥의 결혼",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=141182&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=141182&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/14/11/coversum/8937418460_2.jpg",
             "author": "윌리엄 블레이크 (지은이), 김종철 (옮긴이)",
             "isbn": "9788937418464"
@@ -773,7 +773,7 @@
         "translated_author": "마르쿠스 아우렐리우스",
         "aladin_data": {
             "title": "명상록 - 삶과 죽음을 고뇌한 어느 철학자 황제의 가장 사적인 기록",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=384592083&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=384592083&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/38459/20/coversum/k062135812_1.jpg",
             "author": "마르쿠스 아우렐리우스 (지은이), 정미화 (옮긴이), 그레고리 헤이스 (해제)",
             "isbn": "9791168273993"
@@ -785,7 +785,7 @@
         "translated_author": "아리스토텔레스",
         "aladin_data": {
             "title": "아리스토텔레스 시학 (그리스어 원전 완역본)",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=265596201&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=265596201&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/26559/62/coversum/k392738937_1.jpg",
             "author": "아리스토텔레스 (지은이), 박문재 (옮긴이)",
             "isbn": "9791166812453"
@@ -797,7 +797,7 @@
         "translated_author": "니콜로 마키아벨리",
         "aladin_data": {
             "title": "초판본 군주론 - 오리지널 초판본 표지디자인",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=249432298&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=249432298&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/24943/22/coversum/k032632692_2.jpg",
             "author": "니콜로 마키아벨리 (지은이), 이시연 (옮긴이)",
             "isbn": "9791164453085"
@@ -815,7 +815,7 @@
         "translated_author": "버트런드 러셀",
         "aladin_data": {
             "title": "철학의 문제들 - 전면 개역판",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=385198660&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=385198660&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/38519/86/coversum/8961474928_1.jpg",
             "author": "버트런드 러셀 (지은이), 박영태 (옮긴이)",
             "isbn": "9788961474924"
@@ -827,7 +827,7 @@
         "translated_author": "칼릴 지브란",
         "aladin_data": {
             "title": "예언자",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=129499645&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=129499645&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/12949/96/coversum/k672532485_1.jpg",
             "author": "칼릴 지브란 (지은이), 류시화 (옮긴이)",
             "isbn": "9791186686294"
@@ -839,7 +839,7 @@
         "translated_author": "플라톤",
         "aladin_data": {
             "title": "플라톤의 국가·정체(政體) - 개정 증보판",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=16812&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=16812&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/1/68/coversum/8930606237_2.jpg",
             "author": "플라톤 (지은이), 박종현 (옮긴이)",
             "isbn": "9788930606233"
@@ -851,7 +851,7 @@
         "translated_author": "플라톤",
         "aladin_data": {
             "title": "플라톤의 국가·정체(政體) - 개정 증보판",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=16812&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=16812&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/1/68/coversum/8930606237_2.jpg",
             "author": "플라톤 (지은이), 박종현 (옮긴이)",
             "isbn": "9788930606233"
@@ -875,7 +875,7 @@
         "translated_author": "장 자크 루소",
         "aladin_data": {
             "title": "사회계약론 - 자유와 평등을 위한 약속",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=139172090&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=139172090&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/13917/20/coversum/8961672398_1.jpg",
             "author": "장 자크 루소 (지은이), 권혁 (옮긴이)",
             "isbn": "9788961672399"
@@ -911,7 +911,7 @@
         "translated_author": "아르투어 쇼펜하우어",
         "aladin_data": {
             "title": "의지와 표상으로서의 세계",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=95607072&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=95607072&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/9560/70/coversum/8949714221_2.jpg",
             "author": "아르투어 쇼펜하우어 (지은이), 권기철 (옮긴이)",
             "isbn": "9788949714226"
@@ -923,7 +923,7 @@
         "translated_author": "프리드리히 니체",
         "aladin_data": {
             "title": "차라투스트라는 이렇게 말했다",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=454014&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=454014&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/45/40/coversum/s352934786_1.jpg",
             "author": "프리드리히 니체 (지은이), 장희창 (옮긴이)",
             "isbn": "9788937460944"
@@ -935,7 +935,7 @@
         "translated_author": "존 스튜어트 밀",
         "aladin_data": {
             "title": "공리주의",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=243048009&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=243048009&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/24304/80/coversum/k452630592_1.jpg",
             "author": "존 스튜어트 밀 (지은이), 이종인 (옮긴이)",
             "isbn": "9791190878142"
@@ -947,7 +947,7 @@
         "translated_author": "토머스 모어",
         "aladin_data": {
             "title": "유토피아",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=565805&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=565805&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/56/58/coversum/8974832534_1.jpg",
             "author": "토머스 모어 (지은이), 나종일 (옮긴이)",
             "isbn": "9788974832537"
@@ -959,7 +959,7 @@
         "translated_author": "헨리 데이비드 소로",
         "aladin_data": {
             "title": "월든 - 완결판",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=12840843&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=12840843&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/1284/8/coversum/8956605416_3.jpg",
             "author": "헨리 데이비드 소로 (지은이), 강승영 (옮긴이)",
             "isbn": "9788956605418"
@@ -971,7 +971,7 @@
         "translated_author": "레프 톨스토이",
         "aladin_data": {
             "title": "예술이란 무엇인가",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=319767632&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=319767632&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/31976/76/coversum/k312834367_1.jpg",
             "author": "레프 니콜라예비치 톨스토이 (지은이), 이강은 (옮긴이)",
             "isbn": "9791166891694"
@@ -983,7 +983,7 @@
         "translated_author": "유향",
         "aladin_data": {
             "title": "신서 1",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=6171917&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=6171917&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/617/19/coversum/8949705818_1.jpg",
             "author": "유향 (지은이), 임동석 (옮긴이)",
             "isbn": "9788949705811"
@@ -995,7 +995,7 @@
         "translated_author": "고염무",
         "aladin_data": {
             "title": "원서발췌 일지록",
-            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=383905503&partner=openAPI&start=api",
+            "link": "https://www.aladin.co.kr/shop/wproduct.aspx?ItemId=383905503&partner=openAPI&start=api",
             "thumbnail": "https://image.aladin.co.kr/product/38390/55/coversum/k522135566_1.jpg",
             "author": "고염무 (지은이), 윤대식 (옮긴이)",
             "isbn": "9791143017086"
diff --git a/backend/scripts/generate_book_mapping.py b/backend/scripts/generate_book_mapping.py
index 6af9e45..6f905c7 100644
--- a/backend/scripts/generate_book_mapping.py
+++ b/backend/scripts/generate_book_mapping.py
@@ -111,11 +111,15 @@ async def translate_book_info(file_name: str) -> dict:
                 current_key_idx += 1
             else:
                 print(f"Failed to parse LLM translation for {file_name}: {e}")
-                current_key_idx += 1
+                break
                 
     # If all keys exhausted or other error, fallback
     print(f"LLM Failed for {file_name}, falling back to Kyobo Search...")
-    return await kyobo_fallback(file_name, "")
+    name_without_ext = Path(file_name).stem
+    parts = name_without_ext.rsplit(" by ", 1)
+    fallback_title = parts[0].strip()
+    fallback_author = parts[1].strip() if len(parts) == 2 else ""
+    return await kyobo_fallback(fallback_title, fallback_author)
 
 async def search_aladin(title: str, author: str) -> dict:
     if not ALADIN_API_KEY:
@@ -139,7 +143,7 @@ def fetch():
             item = items[0]
             return {
                 "title": item.get("title", ""),
-                "link": item.get("link", ""),
+                "link": item.get("link", "").replace("&", "&"),
                 "thumbnail": item.get("cover", ""),
                 "author": item.get("author", ""),
                 "isbn": item.get("isbn13", "")
diff --git a/backend/scripts/generate_sql_updates.py b/backend/scripts/generate_sql_updates.py
index 369c518..427d406 100644
--- a/backend/scripts/generate_sql_updates.py
+++ b/backend/scripts/generate_sql_updates.py
@@ -12,9 +12,9 @@ def generate_sql():
     # 1. Create a B-Tree index on the title field to make string matching instant
     # instead of doing a full sequential table scan
     sql_statements = [
+        "CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_documents_book_title ON documents ((metadata->'book_info'->>'title'));\n\n",
         "BEGIN;\n",
-        "CREATE INDEX IF NOT EXISTS idx_documents_book_title ON documents ((metadata->'book_info'->>'title'));\n",
-        "SET statement_timeout = '120s'; -- Increase timeout to be safe\n"
+        "SET LOCAL statement_timeout = '120s'; -- Increase timeout to be safe for this transaction\n"
     ]
     
     for book in mapping_data:
diff --git a/backend/scripts/update_db_metadata.py b/backend/scripts/update_db_metadata.py
index bd77027..2a2bddd 100644
--- a/backend/scripts/update_db_metadata.py
+++ b/backend/scripts/update_db_metadata.py
@@ -85,6 +85,10 @@ def update_database():
         doc_id = doc['id']
         metadata = doc['metadata']
         
+        if not isinstance(metadata, dict):
+            print(f"Skipping doc {doc_id}: metadata is not a dict")
+            continue
+        
         # The DB stores the title we want to match inside metadata->book_info->title
         db_title = metadata.get('book_info', {}).get('title', '')
         
@@ -119,7 +123,7 @@ def update_doc(doc):
                     return True
                 except Exception as e:
                     if attempt < max_retries - 1:
-                        sleep(0.5 * (attempt + 1))  # Exponential backoff
+                        sleep(0.5 * (2 ** attempt))  # Exponential backoff
                         continue
                     print(f"Error updating {doc['id']}: {e}")
                     return False
diff --git a/backend/update_metadata.sql b/backend/update_metadata.sql
index 51b2a24..4114ba9 100644
--- a/backend/update_metadata.sql
+++ b/backend/update_metadata.sql
@@ -1,10 +1,10 @@
-CREATE INDEX IF NOT EXISTS idx_documents_book_title ON documents ((metadata->'book_info'->>'title'));
+CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_documents_book_title ON documents ((metadata->'book_info'->>'title'));
 
 
-SET statement_timeout = '120s'; -- Increase timeout to be safe
-
 BEGIN;
 
+SET LOCAL statement_timeout = '120s'; -- Increase timeout to be safe for this transaction
+
 UPDATE documents
 SET metadata = metadata || '{"kr_title": "역설의 예산 1권", "thumbnail": "", "link": ""}'::jsonb
 WHERE metadata->'book_info'->>'title' = 'Korean Translation of A Budget of Paradoxes Volume I';
diff --git a/frontend/app/page.tsx b/frontend/app/page.tsx
index 6d5a49a..394593f 100644
--- a/frontend/app/page.tsx
+++ b/frontend/app/page.tsx
@@ -3,12 +3,14 @@
 import { useState, useCallback } from "react";
 import { Sidebar } from "../components/sidebar/Sidebar";
 import { ChatMain } from "../components/chat/ChatMain";
-import { Message } from "../types/chat";
+import { Message, DocumentMetadata } from "../types/chat";
 
 export default function Home() {
     const [messages, setMessages] = useState<Message[]>([]);
     const [isSubmitting, setIsSubmitting] = useState(false);
     const [isSidebarOpen, setIsSidebarOpen] = useState(false);
+    const [chatTitle, setChatTitle] = useState<string>("새로운 대화");
+    const [activeMetadata, setActiveMetadata] = useState<DocumentMetadata[]>([]);
 
     const processLine = useCallback((line: string, eventObj: { current: string }, aiMsgId: string): boolean => {
         if (line.startsWith("event: ")) {
@@ -67,13 +69,28 @@ export default function Home() {
         setMessages((prev) => [...prev, newUserMsg, placeholderAiMsg]);
         setIsSubmitting(true);
 
+        const isFirstMessage = messages.length === 0;
+        const baseUrl = process.env.NEXT_PUBLIC_API_BASE_URL || "http://localhost:8000";
+
+        if (isFirstMessage) {
+            fetch(`${baseUrl}/api/v1/chat/title`, {
+                method: "POST",
+                headers: { "Content-Type": "application/json" },
+                body: JSON.stringify({ query: query })
+            })
+                .then(res => res.json())
+                .then(data => {
+                    if (data.title) setChatTitle(data.title);
+                })
+                .catch(err => console.error("Failed to fetch title:", err));
+        }
+
         try {
             const historyToSend = messages.slice(-10).map(msg => ({
                 role: msg.role,
                 content: msg.content
             }));
 
-            const baseUrl = process.env.NEXT_PUBLIC_API_BASE_URL || "http://localhost:8000";
             const res = await fetch(`${baseUrl}/api/v1/chat`, {
                 method: "POST",
                 headers: { "Content-Type": "application/json" },
@@ -152,13 +169,19 @@ export default function Home() {
 
     return (
         <div className="flex h-screen overflow-hidden relative">
-            <Sidebar messages={messages} isOpen={isSidebarOpen} onClose={() => setIsSidebarOpen(false)} />
+            <Sidebar messages={messages} activeMetadata={activeMetadata} isOpen={isSidebarOpen} onClose={() => setIsSidebarOpen(false)} />
             <ChatMain
+                chatTitle={chatTitle}
                 messages={messages}
                 onSendMessage={handleSendMessage}
                 isSubmitting={isSubmitting}
-                onClearChat={() => setMessages([])}
+                onClearChat={() => {
+                    setMessages([]);
+                    setChatTitle("새로운 대화");
+                    setActiveMetadata([]);
+                }}
                 onMenuClick={() => setIsSidebarOpen(true)}
+                onVisibleMessageChange={setActiveMetadata}
             />
         </div>
     );
diff --git a/frontend/components/chat/ChatMain.tsx b/frontend/components/chat/ChatMain.tsx
index c0b87cb..c2a7ed1 100644
--- a/frontend/components/chat/ChatMain.tsx
+++ b/frontend/components/chat/ChatMain.tsx
@@ -4,17 +4,19 @@ import { Share, Plus, Menu } from "lucide-react";
 import { useRef, useEffect, useState } from "react";
 import { MessageList } from "./MessageList";
 import { FloatingInput } from "./FloatingInput";
-import { Message } from "../../types/chat";
+import { Message, DocumentMetadata } from "../../types/chat";
 
 interface ChatMainProps {
     messages: Message[];
+    chatTitle?: string;
     onSendMessage: (query: string) => void;
     isSubmitting: boolean;
     onClearChat: () => void;
     onMenuClick?: () => void;
+    onVisibleMessageChange?: (meta: DocumentMetadata[]) => void;
 }
 
-export function ChatMain({ messages, onSendMessage, isSubmitting, onClearChat, onMenuClick }: ChatMainProps) {
+export function ChatMain({ messages, chatTitle = "새로운 대화", onSendMessage, isSubmitting, onClearChat, onMenuClick, onVisibleMessageChange }: ChatMainProps) {
     const messagesEndRef = useRef<HTMLDivElement>(null);
     const [shouldAutoScroll, setShouldAutoScroll] = useState(true);
     const [startTime, setStartTime] = useState<string>("");
@@ -51,7 +53,7 @@ export function ChatMain({ messages, onSendMessage, isSubmitting, onClearChat, o
                         <Menu className="w-5 h-5" />
                     </button>
                     <div>
-                        <h2 className="font-display text-xl md:text-3xl text-white/90">미덕에 관한 대화</h2>
+                        <h2 className="font-display text-xl md:text-3xl text-white/90 transition-all duration-300">{chatTitle}</h2>
                         <p className="text-xs md:text-sm text-white/40 mt-1">세션 시작: {mounted ? startTime : ""}</p>
                     </div>
                 </div>
@@ -69,7 +71,7 @@ export function ChatMain({ messages, onSendMessage, isSubmitting, onClearChat, o
 
             {/* Scrollable Message Area */}
             <div className="flex-1 overflow-y-auto w-full relative" onScroll={handleScroll}>
-                <MessageList messages={messages} />
+                <MessageList messages={messages} onVisibleMessageChange={onVisibleMessageChange} />
                 <div ref={messagesEndRef} />
             </div>
 
diff --git a/frontend/components/chat/FloatingInput.tsx b/frontend/components/chat/FloatingInput.tsx
index de19f8f..c00ff25 100644
--- a/frontend/components/chat/FloatingInput.tsx
+++ b/frontend/components/chat/FloatingInput.tsx
@@ -37,7 +37,7 @@ export function FloatingInput({ onSendMessage, isSubmitting }: FloatingInputProp
                     <textarea
                         id="chat-input"
                         className="w-full bg-transparent border-0 text-white/90 placeholder-white/30 focus:ring-0 p-0 resize-none font-sans leading-relaxed text-sm md:text-base max-h-32 outline-none"
-                        placeholder="미덕, 형이상학 등에 대해 편하게 물어보세요..."
+                        placeholder="당신의 고민이나 궁금한 점을 편하게 자유롭게 물어보세요..."
                         rows={1}
                         style={{ minHeight: "24px" }}
                         value={inputValue}
diff --git a/frontend/components/chat/MessageList.tsx b/frontend/components/chat/MessageList.tsx
index d71bebb..c33f60a 100644
--- a/frontend/components/chat/MessageList.tsx
+++ b/frontend/components/chat/MessageList.tsx
@@ -1,4 +1,5 @@
 import { Sparkles, SquareArrowOutUpRight, ThumbsUp, Copy, RotateCcw } from "lucide-react";
+import { useEffect, useRef } from "react";
 import { Message, DocumentMetadata } from "../../types/chat";
 
 const DUMMY_COVER_URL = "https://image.aladin.co.kr/product/dummy";
@@ -7,18 +8,91 @@ const DUMMY_BOOK_LINK = "https://www.aladin.co.kr/dummy-link";
 interface Props {
     messages: Message[];
     onOpenCitation?: (meta: DocumentMetadata) => void;
+    onVisibleMessageChange?: (meta: DocumentMetadata[]) => void;
 }
 
-export function MessageList({ messages, onOpenCitation }: Props) {
+export function MessageList({ messages, onOpenCitation, onVisibleMessageChange }: Props) {
+    const observer = useRef<IntersectionObserver | null>(null);
+    const visibleMessages = useRef<Map<string, number>>(new Map());
+
+    useEffect(() => {
+        if (!onVisibleMessageChange) return;
+        visibleMessages.current.clear();
+
+        observer.current = new IntersectionObserver((entries) => {
+            let changed = false;
+            entries.forEach(entry => {
+                const id = entry.target.getAttribute("data-message-id");
+                if (id) {
+                    if (entry.isIntersecting) {
+                        visibleMessages.current.set(id, entry.intersectionRatio);
+                    } else {
+                        visibleMessages.current.delete(id);
+                    }
+                    changed = true;
+                }
+            });
+
+            if (changed) {
+                let maxRatio = -1;
+                let mostVisibleId: string | null = null;
+                visibleMessages.current.forEach((ratio, id) => {
+                    if (ratio > maxRatio) {
+                        maxRatio = ratio;
+                        mostVisibleId = id;
+                    }
+                });
+
+                if (mostVisibleId) {
+                    const emitLatestMetadataOrEmpty = () => {
+                        const aiMessages = messages.filter(m => m.role === "ai" && m.metadata && m.metadata.length > 0);
+                        if (aiMessages.length > 0) {
+                            onVisibleMessageChange(aiMessages[aiMessages.length - 1].metadata!);
+                        } else {
+                            onVisibleMessageChange([]);
+                        }
+                    };
+
+                    const msg = messages.find(m => m.id === mostVisibleId);
+                    if (msg && msg.metadata && msg.metadata.length > 0) {
+                        onVisibleMessageChange(msg.metadata);
+                    } else {
+                        emitLatestMetadataOrEmpty();
+                    }
+                } else {
+                    const emitLatestMetadataOrEmpty = () => {
+                        const aiMessages = messages.filter(m => m.role === "ai" && m.metadata && m.metadata.length > 0);
+                        if (aiMessages.length > 0) {
+                            onVisibleMessageChange(aiMessages[aiMessages.length - 1].metadata!);
+                        } else {
+                            onVisibleMessageChange([]);
+                        }
+                    };
+                    emitLatestMetadataOrEmpty();
+                }
+            }
+        }, {
+            threshold: [0, 0.25, 0.5, 0.75, 1.0]
+        });
+
+        const elements = document.querySelectorAll(".ai-message-card");
+        elements.forEach(el => { observer.current?.observe(el); });
+
+        return () => {
+            observer.current?.disconnect();
+            visibleMessages.current.clear();
+        };
+    }, [messages, onVisibleMessageChange]);
+
     if (messages.length === 0) {
         return (
             <div className="w-full h-full flex flex-col items-center justify-center text-center p-8">
                 <div className="h-16 w-16 rounded-full bg-gradient-to-br from-primary/20 to-transparent border border-primary/30 flex items-center justify-center mb-6 shadow-xl">
                     <Sparkles className="text-primary w-8 h-8" />
                 </div>
-                <h3 className="font-display text-2xl text-white/90 mb-2">어떤 철학적 고민이 있으신가요?</h3>
+                <h3 className="font-display text-2xl text-white/90 mb-2">무엇이 당신을 사유하게 만드나요?</h3>
                 <p className="text-white/50 max-w-md mx-auto text-sm leading-relaxed">
-                    미덕, 죽음, 사랑, 자아 등 삶의 본질적인 질문들을 과거의 위대한 철학자들과 함께 탐구해보세요.
+                    크고 작은 고민부터 삶의 본질적인 질문까지, 위대한 철학자들의 지혜를 통해 새로운 관점을 발견해보세요.
                 </p>
             </div>
         );
@@ -40,7 +114,7 @@ export function MessageList({ messages, onOpenCitation }: Props) {
                             </div>
                         </div>
                     ) : (
-                        <div key={msg.id} className="flex gap-4 md:gap-6 group">
+                        <div key={msg.id} data-message-id={msg.id} className="ai-message-card flex gap-4 md:gap-6 group">
                             <div className="shrink-0 flex flex-col items-center gap-3">
                                 <div className="h-8 w-8 md:h-10 md:w-10 rounded-full bg-gradient-to-br from-[#1a1a1e] to-black border border-primary/30 flex items-center justify-center shadow-[0_0_15px_rgba(217,183,74,0.15)] relative">
                                     <Sparkles className="text-primary w-4 h-4 md:w-5 md:h-5" />
diff --git a/frontend/components/sidebar/ActivePhilosophers.tsx b/frontend/components/sidebar/ActivePhilosophers.tsx
index 10ea5b0..9b2410f 100644
--- a/frontend/components/sidebar/ActivePhilosophers.tsx
+++ b/frontend/components/sidebar/ActivePhilosophers.tsx
@@ -2,48 +2,67 @@ import { BrainCircuit, CheckCircle } from "lucide-react";
 import { DocumentMetadata } from "../../types/chat";
 
 interface Props {
-    metadata: DocumentMetadata[];
+    metadata: DocumentMetadata[]; // all seen philosophers
+    activeMetadata?: DocumentMetadata[]; // active philosophers
     onPhilosopherClick?: (scholar: string) => void;
 }
 
-export function ActivePhilosophers({ metadata, onPhilosopherClick }: Props) {
+export function ActivePhilosophers({ metadata, activeMetadata = [], onPhilosopherClick }: Props) {
     const uniquePhilosophers = Array.from(new Set(metadata.map(m => m.scholar)))
         .map(scholar => metadata.find(m => m.scholar === scholar))
         .filter((m): m is DocumentMetadata => m !== undefined);
 
+    const activeScholarSet = new Set(activeMetadata.map(m => m.scholar));
+
+    // Sort to put highlighted philosophers at the top
+    const sortedPhilosophers = [...uniquePhilosophers].sort((a, b) => {
+        const aActive = activeScholarSet.has(a.scholar);
+        const bActive = activeScholarSet.has(b.scholar);
+        if (aActive && !bActive) return -1;
+        if (!aActive && bActive) return 1;
+        return 0;
+    });
+
     return (
         <div>
             <h3 className="text-xs font-medium text-primary uppercase tracking-widest mb-4 flex items-center gap-2">
                 <BrainCircuit className="w-4 h-4" />
                 활성화된 철학자
             </h3>
-            {uniquePhilosophers.length === 0 ? (
+            {sortedPhilosophers.length === 0 ? (
                 <p className="text-white/30 text-xs italic">현재 참조 중인 철학자가 없습니다.</p>
             ) : (
                 <div className="space-y-3">
-                    {uniquePhilosophers.map((meta) => (
-                        <button
-                            key={meta.scholar}
-                            type="button"
-                            onClick={() => onPhilosopherClick?.(meta.scholar)}
-                            className="w-full text-left group relative overflow-hidden rounded-xl border border-white/10 bg-white/5 p-4 hover:border-primary/50 transition-all duration-300 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-primary/60"
-                        >
-                            <div className="absolute inset-0 bg-gradient-to-r from-primary/5 to-transparent opacity-0 group-hover:opacity-100 transition-opacity"></div>
-                            <div className="relative flex items-center gap-4">
-                                <div
-                                    className="h-12 w-12 shrink-0 rounded-full border border-white/20 bg-gradient-to-br from-white/10 to-transparent flex items-center justify-center shadow-inner"
-                                    title={meta.scholar}
-                                >
-                                    <span className="font-display text-xl text-primary/90">{meta.scholar.charAt(0)}</span>
-                                </div>
-                                <div className="flex-1">
-                                    <h4 className="font-display text-lg text-white">{meta.scholar}</h4>
-                                    <p className="text-xs text-white/50">{meta.school}</p>
+                    {sortedPhilosophers.map((meta) => {
+                        const isActive = activeScholarSet.has(meta.scholar);
+                        return (
+                            <button
+                                key={meta.scholar}
+                                type="button"
+                                onClick={() => onPhilosopherClick?.(meta.scholar)}
+                                className={`w-full text-left group relative overflow-hidden rounded-xl border p-4 transition-all duration-300 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-primary/60
+                                    ${isActive
+                                        ? "border-primary/50 bg-primary/10 shadow-[0_0_15px_rgba(217,183,74,0.1)]"
+                                        : "border-white/10 bg-white/5 hover:border-primary/30"
+                                    }`}
+                            >
+                                <div className={`absolute inset-0 bg-gradient-to-r ${isActive ? "from-primary/10" : "from-primary/5"} to-transparent opacity-0 group-hover:opacity-100 transition-opacity`}></div>
+                                <div className="relative flex items-center gap-4">
+                                    <div
+                                        className={`h-12 w-12 shrink-0 rounded-full border ${isActive ? "border-primary/30" : "border-white/20"} bg-gradient-to-br from-white/10 to-transparent flex items-center justify-center shadow-inner`}
+                                        title={meta.scholar}
+                                    >
+                                        <span className={`font-display text-xl ${isActive ? "text-primary/90" : "text-white/70"}`}>{meta.scholar.charAt(0)}</span>
+                                    </div>
+                                    <div className="flex-1">
+                                        <h4 className={`font-display text-lg ${isActive ? "text-white" : "text-white/80"}`}>{meta.scholar}</h4>
+                                        <p className={`text-xs ${isActive ? "text-white/60" : "text-white/40"}`}>{meta.school}</p>
+                                    </div>
+                                    <CheckCircle className={`ml-auto w-5 h-5 shrink-0 transition-colors ${isActive ? "text-primary" : "text-primary/20 group-hover:text-primary/50"}`} />
                                 </div>
-                                <CheckCircle className="ml-auto text-primary/50 group-hover:text-primary w-5 h-5 shrink-0" />
-                            </div>
-                        </button>
-                    ))}
+                            </button>
+                        );
+                    })}
                 </div>
             )}
         </div>
diff --git a/frontend/components/sidebar/Sidebar.tsx b/frontend/components/sidebar/Sidebar.tsx
index 786fece..8c088d0 100644
--- a/frontend/components/sidebar/Sidebar.tsx
+++ b/frontend/components/sidebar/Sidebar.tsx
@@ -1,18 +1,47 @@
 import { Settings, History, User, X } from "lucide-react";
+import { useState } from "react";
 import { ActivePhilosophers } from "./ActivePhilosophers";
 import { ContextSources } from "./ContextSources";
-import { Message } from "../../types/chat";
+import { Message, DocumentMetadata } from "../../types/chat";
 
 interface SidebarProps {
     messages?: Message[];
+    activeMetadata?: DocumentMetadata[];
     isOpen?: boolean;
     onClose?: () => void;
 }
 
-export function Sidebar({ messages = [], isOpen = false, onClose }: SidebarProps) {
+export function Sidebar({ messages = [], activeMetadata = [], isOpen = false, onClose }: SidebarProps) {
+    const [filterScholar, setFilterScholar] = useState<string | null>(null);
+
     const aiMessages = messages.filter(m => m.role === "ai" && m.metadata && m.metadata.length > 0);
     const currentMetadata = aiMessages.length > 0 ? aiMessages[aiMessages.length - 1].metadata! : [];
 
+    // All unique metadata observed throughout the chat so far, deduplicated by id
+    const allMetadata = Array.from(
+        new Map(
+            aiMessages
+                .flatMap(m => m.metadata || [])
+                .map(meta => [meta.id, meta])
+        ).values()
+    );
+
+    // Use active metadata from scroll if available, otherwise use latest message's metadata
+    let displayMetadata = activeMetadata.length > 0 ? activeMetadata : currentMetadata;
+
+    // Apply philosophy/scholar filter if active
+    if (filterScholar) {
+        displayMetadata = allMetadata.filter(meta => meta.scholar === filterScholar);
+    }
+
+    const handlePhilosopherClick = (scholar: string) => {
+        if (filterScholar === scholar) {
+            setFilterScholar(null); // Clear filter if clicking the already active one
+        } else {
+            setFilterScholar(scholar);
+        }
+    };
+
     return (
         <>
             {/* Mobile Overlay */}
@@ -46,8 +75,8 @@ export function Sidebar({ messages = [], isOpen = false, onClose }: SidebarProps
 
                 {/* Scrollable Content */}
                 <div className="flex-1 overflow-y-auto p-6 space-y-8">
-                    <ActivePhilosophers metadata={currentMetadata} onPhilosopherClick={() => { /* TODO: Implement philosopher filter using scholar */ }} />
-                    <ContextSources metadata={currentMetadata} />
+                    <ActivePhilosophers metadata={allMetadata} activeMetadata={displayMetadata} onPhilosopherClick={handlePhilosopherClick} />
+                    <ContextSources metadata={displayMetadata} />
                 </div>
 
                 {/* System Status */}