diff --git a/docs/images/streamlit.png b/docs/images/streamlit.png
index b3162f0..a7959e0 100644
Binary files a/docs/images/streamlit.png and b/docs/images/streamlit.png differ
diff --git a/docs/index.ja.md b/docs/index.ja.md
index 871ddaa..6663b6f 100644
--- a/docs/index.ja.md
+++ b/docs/index.ja.md
@@ -222,7 +222,7 @@ uv run streamlit run \
 
 Streamlit アプリのデモ：
 
-[![streamlit.png](./images/streamlit.png)](https://youtu.be/z7QhEsqIGAk)
+[![streamlit.png](./images/streamlit.png)](https://youtu.be/undxBwyJ3Sc)
 
 ## 実演されている主要概念
 
diff --git a/docs/index.md b/docs/index.md
index dd98fe1..795a04c 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -222,7 +222,7 @@ uv run streamlit run \
 
 Demonstration of the Streamlit app:
 
-[![streamlit.png](./images/streamlit.png)](https://youtu.be/z7QhEsqIGAk)
+[![streamlit.png](./images/streamlit.png)](https://youtu.be/undxBwyJ3Sc)
 
 ## Key Concepts Demonstrated
 
diff --git a/template_langgraph/services/streamlits/pages/chat_with_tools_agent.py b/template_langgraph/services/streamlits/pages/chat_with_tools_agent.py
index f01c749..e9562e7 100644
--- a/template_langgraph/services/streamlits/pages/chat_with_tools_agent.py
+++ b/template_langgraph/services/streamlits/pages/chat_with_tools_agent.py
@@ -3,11 +3,44 @@
     StreamlitCallbackHandler,
 )
 
-from template_langgraph.agents.chat_with_tools_agent.agent import AgentState, graph
+from template_langgraph.agents.chat_with_tools_agent.agent import (
+    AgentState,
+    ChatWithToolsAgent,
+)
+from template_langgraph.tools.common import get_default_tools
 
 if "chat_history" not in st.session_state:
     st.session_state["chat_history"] = []
 
+# Sidebar: ツール選択とエージェントの構築
+with st.sidebar:
+    st.subheader("使用するツール")
+
+    # 利用可能なツール一覧を取得
+    available_tools = get_default_tools()
+    tool_name_to_obj = {t.name: t for t in available_tools}
+    tool_names = list(tool_name_to_obj.keys())
+
+    # 初期選択は全選択
+    if "selected_tool_names" not in st.session_state:
+        st.session_state["selected_tool_names"] = tool_names
+
+    selected_tool_names = st.multiselect(
+        "有効化するツールを選択",
+        options=tool_names,
+        default=st.session_state["selected_tool_names"],
+    )
+    st.session_state["selected_tool_names"] = selected_tool_names
+
+    # 選択されたツールでグラフを再構築（選択が変わった時のみ）
+    selected_tools = [tool_name_to_obj[name] for name in selected_tool_names]
+    signature = tuple(selected_tool_names)
+    if "graph" not in st.session_state or st.session_state.get("graph_tools_signature") != signature:
+        st.session_state["graph"] = ChatWithToolsAgent(tools=selected_tools).create_graph()
+        st.session_state["graph_tools_signature"] = signature
+    # 選択中のツール表示（簡易）
+    st.caption("選択中: " + (", ".join(selected_tool_names) if selected_tool_names else "なし"))
+
 for msg in st.session_state["chat_history"]:
     if isinstance(msg, dict):
         st.chat_message(msg["role"]).write(msg["content"])
@@ -18,7 +51,7 @@
     st.session_state["chat_history"].append({"role": "user", "content": prompt})
     st.chat_message("user").write(prompt)
     with st.chat_message("assistant"):
-        response: AgentState = graph.invoke(
+        response: AgentState = st.session_state["graph"].invoke(
             {"messages": st.session_state["chat_history"]},
             {
                 "callbacks": [
@@ -26,5 +59,6 @@
                 ]
             },
         )
-        st.session_state["chat_history"].append(response["messages"][-1])
-        st.write(response["messages"][-1].content)
+        last_message = response["messages"][-1]
+        st.session_state["chat_history"].append(last_message)
+        st.write(last_message.content)