diff --git a/README.md b/README.md
index a6442e4..0640ded 100644
--- a/README.md
+++ b/README.md
@@ -16,6 +16,7 @@
 ## 🌟 核心特性
 
 - **🗣️ 自然语言转 SQL**: 用大白话提问！它能理解你的数据表结构，生成准确的 SQL，甚至在报错时进行自我纠正 (Self-correction)。
+- **📚 智能知识库检索 (RAG)**: 支持上传 Word、PPT、PDF 等多种格式文档，通过向量检索增强回答，让你的私有文档“开口说话”。
 - **📈 即时数据可视化**: 拒绝枯燥的生肉表格，根据数据特征自动生成交互式图表。
 - **🗂️ 动态多数据源**: 无缝连接 PostgreSQL、Supabase，以及本地 CSV/Excel 文件上传解析。
 - **🧠 灵活的模型接入**: 原生集成 LiteLLM，支持随插随用 OpenAI、DeepSeek、智谱、通义千问 (DashScope)、火山引擎或任何兼容的 LLM 提供商。
@@ -27,17 +28,21 @@
 
 ## 📸 界面预览
 
-<div align="center">
-  <h3>对话式分析界面</h3>
-  <img src="./examples/index.png" width="80%" />
+<div align="left">
+  <h3>💬 对话式分析界面</h3>
+  <img src="./docs/index.png" width="80%" />
   <br />
   <br />
-  <h3>可定制仪表盘</h3>
-  <img src="./examples/dashboard.png" width="80%" />
+  <h3>📊 可定制仪表盘</h3>
+  <img src="./docs/dashboard.png" width="80%" />
   <br />
   <br />
-  <h3>智能产物预览 (Artifact)</h3>
-  <img src="./examples/artifact.png" width="80%" />
+  <h3>📚 智能知识库问答</h3>
+  <img src="./docs/kb.png" width="80%" />
+  <br />
+  <br />
+  <h3>📦 智能产物预览 (Artifact)</h3>
+  <img src="./docs/artifact.png" width="80%" />
 </div>
 
 <br />
diff --git a/README_en.md b/README_en.md
index e8eb4ed..a31da56 100644
--- a/README_en.md
+++ b/README_en.md
@@ -16,6 +16,7 @@ Whether you're querying a massive Supabase/PostgreSQL database or just tossing i
 ## 🌟 Key Features
 
 - **🗣️ Chat to SQL**: Ask questions in plain English (or Chinese!). DataClaw understands your schema, generates accurate SQL, and self-corrects if things go sideways.
+- **📚 Smart Knowledge Base (RAG)**: Support uploading Word, PPT, PDF and other document formats. Enhance answers through vector retrieval, making your private documents "speak".
 - **📈 Instant Visualizations**: Returns not just raw tables, but auto-generated interactive charts tailored to your data's shape.
 - **🗂️ Multi-Source Ready**: Connects seamlessly to PostgreSQL, Supabase, and local CSV/Excel uploads.
 - **🧠 Bring Your Own LLM**: Native integration with LiteLLM. Plug in OpenAI, DeepSeek, Zhipu, DashScope, Volcengine, or any compatible provider.
@@ -27,17 +28,21 @@ Whether you're querying a massive Supabase/PostgreSQL database or just tossing i
 
 ## 📸 Screenshots
 
-<div align="center">
-  <h3>Chat Interface</h3>
-  <img src="./examples/index.png" width="80%" />
+<div align="left">
+  <h3>💬 Chat Interface</h3>
+  <img src="./docs/index.png" width="80%" />
   <br />
   <br />
-  <h3>Customizable Dashboard</h3>
-  <img src="./examples/dashboard.png" width="80%" />
+  <h3>📊 Customizable Dashboard</h3>
+  <img src="./docs/dashboard.png" width="80%" />
   <br />
   <br />
-  <h3>Artifact Preview</h3>
-  <img src="./examples/artifact.png" width="80%" />
+  <h3>📚 Smart Knowledge Base</h3>
+  <img src="./docs/kb.png" width="80%" />
+  <br />
+  <br />
+  <h3>📦 Artifact Preview</h3>
+  <img src="./docs/artifact.png" width="80%" />
 </div>
 
 <br />
diff --git a/examples/artifact.png b/docs/artifact.png
similarity index 100%
rename from examples/artifact.png
rename to docs/artifact.png
diff --git a/examples/dashboard.png b/docs/dashboard.png
similarity index 100%
rename from examples/dashboard.png
rename to docs/dashboard.png
diff --git a/examples/index.png b/docs/index.png
similarity index 100%
rename from examples/index.png
rename to docs/index.png
diff --git a/docs/kb.png b/docs/kb.png
new file mode 100644
index 0000000..7af3ffe
Binary files /dev/null and b/docs/kb.png differ
diff --git a/examples/Car_Database.db b/examples/Car_Database.db
deleted file mode 100644
index e7334bc..0000000
Binary files a/examples/Car_Database.db and /dev/null differ
diff --git a/examples/file_example_XLS_1000.xls b/examples/file_example_XLS_1000.xls
deleted file mode 100644
index af70880..0000000
Binary files a/examples/file_example_XLS_1000.xls and /dev/null differ
diff --git a/frontend/src/components/ChatInterface.tsx b/frontend/src/components/ChatInterface.tsx
index ce0eb63..d277fa3 100644
--- a/frontend/src/components/ChatInterface.tsx
+++ b/frontend/src/components/ChatInterface.tsx
@@ -328,7 +328,20 @@ export function ChatInterface() {
   // Model selection state
   const [models, setModels] = useState<ModelConfig[]>([]);
   const [selectedModelId, setSelectedModelId] = useState<string>("");
-  const [modelOpen, setModelOpen] = useState(false);
+
+  // Listen for model changes from the ProjectSwitcher
+  useEffect(() => {
+    const handleModelChange = (e: Event) => {
+      const customEvent = e as CustomEvent<string>;
+      if (customEvent.detail) {
+        setSelectedModelId(customEvent.detail);
+      }
+    };
+    window.addEventListener('nanobot:model-changed', handleModelChange);
+    return () => {
+      window.removeEventListener('nanobot:model-changed', handleModelChange);
+    };
+  }, []);
   
   // Data Source selection state
   const [availableDataSources, setAvailableDataSources] = useState<{id: string, name: string}[]>([]);
@@ -1120,49 +1133,6 @@ export function ChatInterface() {
 
   return (
     <div className="flex flex-col h-full bg-background relative">
-      {/* Header with Model Selection */}
-      <div className="px-4 py-3 flex items-center justify-between border-b border-border bg-background/50 backdrop-blur-md sticky top-0 z-20">
-        <Popover open={modelOpen} onOpenChange={setModelOpen}>
-          <PopoverTrigger className="flex items-center gap-2 px-3 py-1.5 rounded-lg hover:bg-muted transition-colors group">
-            <span className="font-semibold text-foreground">
-              {selectedModelId ? models.find(m => m.id === selectedModelId)?.name || 'DataClaw' : 'DataClaw'}
-            </span>
-            <ChevronDown className="h-4 w-4 text-muted-foreground group-hover:text-muted-foreground transition-colors" />
-          </PopoverTrigger>
-          <PopoverContent className="w-[280px] p-0" align="start">
-            <Command>
-              <CommandInput placeholder={t('searchModel')} />
-              <CommandList className="max-h-[300px]">
-                <CommandEmpty>{t('modelNotFound')}</CommandEmpty>
-                <CommandGroup heading={t('availableModels')}>
-                  {models.map((model) => (
-                    <CommandItem
-                      key={model.id}
-                      onSelect={() => {
-                        setSelectedModelId(model.id);
-                        setModelOpen(false);
-                      }}
-                      className="flex items-center gap-2 py-2.5 cursor-pointer"
-                    >
-                      <div className="flex flex-col">
-                        <span className="font-medium text-foreground">{model.name || model.model}</span>
-                        <span className="text-xs text-muted-foreground">{model.provider}</span>
-                      </div>
-                      <Check
-                        className={cn(
-                          "ml-auto h-4 w-4",
-                          selectedModelId === model.id ? "opacity-100" : "opacity-0"
-                        )}
-                      />
-                    </CommandItem>
-                  ))}
-                </CommandGroup>
-              </CommandList>
-            </Command>
-          </PopoverContent>
-        </Popover>
-      </div>
-
       <ScrollArea className="flex-1 min-h-0">
         {/* Hidden file input available in all states */}
         <input
diff --git a/frontend/src/components/ProjectSwitcher.tsx b/frontend/src/components/ProjectSwitcher.tsx
index c65c361..ade275f 100644
--- a/frontend/src/components/ProjectSwitcher.tsx
+++ b/frontend/src/components/ProjectSwitcher.tsx
@@ -1,6 +1,9 @@
 import { useEffect, useState } from 'react';
-import { ChevronDown, Plus, Folder } from 'lucide-react';
+import { ChevronDown, Plus, Folder, Check } from 'lucide-react';
 import { useProjectStore } from '@/store/projectStore';
+import { useTranslation } from "react-i18next";
+import { api } from "@/lib/api";
+import { cn } from "@/lib/utils";
 import {
   DropdownMenu,
   DropdownMenuContent,
@@ -14,17 +17,51 @@ import { Button } from '@/components/ui/button';
 import { Dialog, DialogContent, DialogHeader, DialogTitle, DialogFooter } from '@/components/ui/dialog';
 import { Input } from '@/components/ui/input';
 import { Label } from '@/components/ui/label';
+import { Popover, PopoverContent, PopoverTrigger } from '@/components/ui/popover';
+import { Command, CommandEmpty, CommandGroup, CommandInput, CommandItem, CommandList } from '@/components/ui/command';
+
+interface ModelConfig {
+  id: string;
+  name: string;
+  model: string;
+  provider: string;
+  is_active: boolean;
+}
 
 export function ProjectSwitcher() {
+  const { t } = useTranslation();
   const { projects, currentProject, fetchProjects, setCurrentProject, addProject } = useProjectStore();
   const [isCreateDialogOpen, setIsCreateDialogOpen] = useState(false);
   const [newProjectName, setNewProjectName] = useState('');
   const [isSubmitting, setIsSubmitting] = useState(false);
 
+  // Model Selection State
+  const [models, setModels] = useState<ModelConfig[]>([]);
+  const [selectedModelId, setSelectedModelId] = useState<string>("");
+  const [modelOpen, setModelOpen] = useState(false);
+
   useEffect(() => {
     fetchProjects();
   }, [fetchProjects]);
 
+  useEffect(() => {
+    const fetchModels = async () => {
+      try {
+        const data = await api.get<ModelConfig[]>("/api/v1/llm");
+        setModels(data);
+        const active = data.find(m => m.is_active);
+        if (active) {
+          setSelectedModelId(active.id);
+        } else if (data.length > 0) {
+          setSelectedModelId(data[0].id);
+        }
+      } catch (e) {
+        console.error("Failed to fetch models", e);
+      }
+    };
+    fetchModels();
+  }, []);
+
   const handleCreateProject = async () => {
     if (!newProjectName.trim()) return;
     setIsSubmitting(true);
@@ -88,6 +125,50 @@ export function ProjectSwitcher() {
         </DropdownMenuContent>
       </DropdownMenu>
 
+      <div className="h-4 w-px bg-border mx-1" />
+
+      <Popover open={modelOpen} onOpenChange={setModelOpen}>
+        <PopoverTrigger className="flex items-center gap-1 px-2 py-1 rounded-md hover:bg-accent hover:text-accent-foreground transition-colors group">
+          <span className="font-semibold text-[14px]">
+            {selectedModelId ? (models.find(m => m.id === selectedModelId)?.name || models.find(m => m.id === selectedModelId)?.model || 'DataClaw') : 'DataClaw'}
+          </span>
+          <ChevronDown className="h-4 w-4 opacity-50 group-hover:opacity-100 transition-colors" />
+        </PopoverTrigger>
+        <PopoverContent className="w-[280px] p-0" align="start">
+          <Command>
+            <CommandInput placeholder={t('searchModel')} />
+            <CommandList className="max-h-[300px]">
+              <CommandEmpty>{t('modelNotFound')}</CommandEmpty>
+              <CommandGroup heading={t('availableModels')}>
+                {models.map((model) => (
+                  <CommandItem
+                    key={model.id}
+                    onSelect={() => {
+                      setSelectedModelId(model.id);
+                      setModelOpen(false);
+                      // Fire custom event to notify ChatInterface if needed
+                      window.dispatchEvent(new CustomEvent("nanobot:model-changed", { detail: model.id }));
+                    }}
+                    className="flex items-center gap-2 py-2.5 cursor-pointer"
+                  >
+                    <div className="flex flex-col">
+                      <span className="font-medium text-foreground">{model.name || model.model}</span>
+                      <span className="text-xs text-muted-foreground">{model.provider}</span>
+                    </div>
+                    <Check
+                      className={cn(
+                        "ml-auto h-4 w-4",
+                        selectedModelId === model.id ? "opacity-100" : "opacity-0"
+                      )}
+                    />
+                  </CommandItem>
+                ))}
+              </CommandGroup>
+            </CommandList>
+          </Command>
+        </PopoverContent>
+      </Popover>
+
       <Dialog open={isCreateDialogOpen} onOpenChange={setIsCreateDialogOpen}>
         <DialogContent>
           <DialogHeader>