diff --git a/api/app/routers/tools.py b/api/app/routers/tools.py
index eab3f91..b0087a7 100644
--- a/api/app/routers/tools.py
+++ b/api/app/routers/tools.py
@@ -87,6 +87,17 @@ TOOL_REGISTRY = {
             "required": []
         }
     },
+    "voice_message_prompt": {
+        "name": "语音消息提示",
+        "description": "播报一条语音提示消息",
+        "parameters": {
+            "type": "object",
+            "properties": {
+                "msg": {"type": "string", "description": "要播报的消息文本"}
+            },
+            "required": ["msg"]
+        }
+    },
 }
 
 TOOL_CATEGORY_MAP = {
@@ -97,6 +108,7 @@ TOOL_CATEGORY_MAP = {
     "turn_off_camera": "system",
     "increase_volume": "system",
     "decrease_volume": "system",
+    "voice_message_prompt": "system",
 }
 
 TOOL_ICON_MAP = {
@@ -107,6 +119,7 @@ TOOL_ICON_MAP = {
     "turn_off_camera": "CameraOff",
     "increase_volume": "Volume2",
     "decrease_volume": "Volume2",
+    "voice_message_prompt": "Volume2",
 }
 
 TOOL_HTTP_DEFAULTS = {
@@ -185,11 +198,16 @@ def _validate_query_http_config(*, category: str, tool_id: Optional[str], http_u
 
 
 def _seed_default_tools_if_empty(db: Session) -> None:
-    """Seed built-in tools only when tool_resources is empty."""
+    """Ensure built-in tools exist in tool_resources without overriding custom edits."""
     _ensure_tool_resource_schema(db)
-    if db.query(ToolResource).count() > 0:
-        return
+    existing_ids = {
+        str(item[0])
+        for item in db.query(ToolResource.id).all()
+    }
+    changed = False
     for tool_id, payload in TOOL_REGISTRY.items():
+        if tool_id in existing_ids:
+            continue
         http_defaults = TOOL_HTTP_DEFAULTS.get(tool_id, {})
         db.add(ToolResource(
             id=tool_id,
@@ -207,7 +225,9 @@ def _seed_default_tools_if_empty(db: Session) -> None:
             enabled=True,
             is_system=True,
         ))
-    db.commit()
+        changed = True
+    if changed:
+        db.commit()
 
 
 def recreate_tool_resources(db: Session) -> None:
diff --git a/engine/core/duplex_pipeline.py b/engine/core/duplex_pipeline.py
index 3f5be85..858e5cd 100644
--- a/engine/core/duplex_pipeline.py
+++ b/engine/core/duplex_pipeline.py
@@ -146,12 +146,24 @@ class DuplexPipeline:
                 "required": [],
             },
         },
+        "voice_message_prompt": {
+            "name": "voice_message_prompt",
+            "description": "Speak a message prompt on client side",
+            "parameters": {
+                "type": "object",
+                "properties": {
+                    "msg": {"type": "string", "description": "Message text to speak"},
+                },
+                "required": ["msg"],
+            },
+        },
     }
     _DEFAULT_CLIENT_EXECUTORS = frozenset({
         "turn_on_camera",
         "turn_off_camera",
         "increase_volume",
         "decrease_volume",
+        "voice_message_prompt",
     })
 
     def __init__(
diff --git a/web/pages/Assistants.tsx b/web/pages/Assistants.tsx
index 7a1ba6f..f3122e0 100644
--- a/web/pages/Assistants.tsx
+++ b/web/pages/Assistants.tsx
@@ -1682,6 +1682,13 @@ const TOOL_PARAMETER_HINTS: Record<string, any> = {
     },
     required: [],
   },
+  voice_message_prompt: {
+    type: 'object',
+    properties: {
+      msg: { type: 'string', description: 'Message text to speak' },
+    },
+    required: ['msg'],
+  },
   code_interpreter: {
     type: 'object',
     properties: {
@@ -1694,6 +1701,15 @@ const TOOL_PARAMETER_HINTS: Record<string, any> = {
 const getDefaultToolParameters = (toolId: string) =>
   TOOL_PARAMETER_HINTS[toolId] || { type: 'object', properties: {} };
 
+const DEBUG_CLIENT_TOOLS = [
+  { id: 'turn_on_camera', name: 'turn_on_camera', description: '打开摄像头' },
+  { id: 'turn_off_camera', name: 'turn_off_camera', description: '关闭摄像头' },
+  { id: 'increase_volume', name: 'increase_volume', description: '调高音量' },
+  { id: 'decrease_volume', name: 'decrease_volume', description: '调低音量' },
+  { id: 'voice_message_prompt', name: 'voice_message_prompt', description: '语音消息提示' },
+] as const;
+const DEBUG_CLIENT_TOOL_ID_SET = new Set<string>(DEBUG_CLIENT_TOOLS.map((item) => item.id));
+
 type DynamicVariableEntry = {
   id: string;
   key: string;
@@ -2034,6 +2050,13 @@ export const DebugDrawer: React.FC<{
   const [aecEnabled, setAecEnabled] = useState<boolean>(() => localStorage.getItem('debug_audio_aec') !== '0');
   const [nsEnabled, setNsEnabled] = useState<boolean>(() => localStorage.getItem('debug_audio_ns') !== '0');
   const [agcEnabled, setAgcEnabled] = useState<boolean>(() => localStorage.getItem('debug_audio_agc') !== '0');
+  const [clientToolEnabledMap, setClientToolEnabledMap] = useState<Record<string, boolean>>(() => {
+    const result: Record<string, boolean> = {};
+    for (const tool of DEBUG_CLIENT_TOOLS) {
+      result[tool.id] = localStorage.getItem(`debug_client_tool_enabled_${tool.id}`) !== '0';
+    }
+    return result;
+  });
 
   const micAudioCtxRef = useRef<AudioContext | null>(null);
   const micSourceRef = useRef<MediaStreamAudioSourceNode | null>(null);
@@ -2043,14 +2066,18 @@ export const DebugDrawer: React.FC<{
   const userDraftIndexRef = useRef<number | null>(null);
   const lastUserFinalRef = useRef<string>('');
   const debugVolumePercentRef = useRef<number>(50);
+  const isClientToolEnabled = (toolId: string) => clientToolEnabledMap[toolId] !== false;
   const selectedToolSchemas = useMemo(() => {
-    const ids = assistant.tools || [];
-    if (!ids.length) return [];
+    const ids = Array.from(new Set([...(assistant.tools || []), ...DEBUG_CLIENT_TOOLS.map((item) => item.id)]));
     const byId = new Map(tools.map((t) => [t.id, t]));
     return ids.map((id) => {
       const item = byId.get(id);
       const toolId = item?.id || id;
-      const isClientTool = (item?.category || 'query') === 'system';
+      const debugClientTool = DEBUG_CLIENT_TOOLS.find((tool) => tool.id === toolId);
+      if (debugClientTool && !isClientToolEnabled(toolId)) {
+        return null;
+      }
+      const isClientTool = debugClientTool ? true : (item?.category || 'query') === 'system';
       const parameterSchema = (item?.parameterSchema && typeof item.parameterSchema === 'object')
         ? item.parameterSchema
         : getDefaultToolParameters(toolId);
@@ -2063,12 +2090,12 @@ export const DebugDrawer: React.FC<{
         ...(parameterDefaults && Object.keys(parameterDefaults).length > 0 ? { defaultArgs: parameterDefaults } : {}),
         function: {
           name: toolId,
-          description: item?.description || item?.name || id,
+          description: item?.description || item?.name || debugClientTool?.description || id,
           parameters: parameterSchema,
         },
       };
-    });
-  }, [assistant.tools, tools]);
+    }).filter(Boolean) as Array<Record<string, any>>;
+  }, [assistant.tools, tools, clientToolEnabledMap]);
 
   const clearResponseTracking = () => {
     assistantDraftIndexRef.current = null;
@@ -2129,6 +2156,12 @@ export const DebugDrawer: React.FC<{
     localStorage.setItem('debug_audio_agc', agcEnabled ? '1' : '0');
   }, [agcEnabled]);
 
+  useEffect(() => {
+    for (const tool of DEBUG_CLIENT_TOOLS) {
+      localStorage.setItem(`debug_client_tool_enabled_${tool.id}`, isClientToolEnabled(tool.id) ? '1' : '0');
+    }
+  }, [clientToolEnabledMap]);
+
   // Auto-scroll logic
   useEffect(() => {
       if (scrollRef.current) {
@@ -2940,6 +2973,10 @@ export const DebugDrawer: React.FC<{
               output: { message: `Unhandled client tool '${toolName}'` },
               status: { code: 501, message: 'not_implemented' },
             };
+            if (DEBUG_CLIENT_TOOL_ID_SET.has(toolName) && !isClientToolEnabled(toolName)) {
+              resultPayload.output = { message: `Client tool '${toolName}' is disabled in debug settings` };
+              resultPayload.status = { code: 503, message: 'tool_disabled' };
+            }
             const sendToolResult = () => {
               ws.send(
                 JSON.stringify({
@@ -2962,7 +2999,9 @@ export const DebugDrawer: React.FC<{
               ]);
             };
             try {
-              if (toolName === 'turn_on_camera') {
+              if (resultPayload.status.code === 503) {
+                // Keep disabled result as-is.
+              } else if (toolName === 'turn_on_camera') {
                 navigator.mediaDevices
                   .getUserMedia({
                     video: selectedCamera ? { deviceId: { exact: selectedCamera } } : true,
@@ -3010,6 +3049,22 @@ export const DebugDrawer: React.FC<{
                   level: debugVolumePercentRef.current,
                 };
                 resultPayload.status = { code: 200, message: 'ok' };
+              } else if (toolName === 'voice_message_prompt') {
+                const msg = String(parsedArgs?.msg || '').trim();
+                if (!msg) {
+                  resultPayload.output = { message: "Missing required argument 'msg'" };
+                  resultPayload.status = { code: 422, message: 'invalid_arguments' };
+                } else if (typeof window !== 'undefined' && 'speechSynthesis' in window) {
+                  const utterance = new SpeechSynthesisUtterance(msg);
+                  utterance.lang = 'zh-CN';
+                  window.speechSynthesis.cancel();
+                  window.speechSynthesis.speak(utterance);
+                  resultPayload.output = { message: 'voice_prompt_sent', msg };
+                  resultPayload.status = { code: 200, message: 'ok' };
+                } else {
+                  resultPayload.output = { message: 'speech_synthesis_unavailable', msg };
+                  resultPayload.status = { code: 503, message: 'speech_output_unavailable' };
+                }
               }
             } catch (err) {
               resultPayload.output = {
@@ -3381,6 +3436,33 @@ export const DebugDrawer: React.FC<{
             Auto Gain Control (AGC)
           </label>
         </div>
+        <div className="rounded-md border border-white/10 bg-black/20 p-2 space-y-2">
+          <p className="text-[10px] uppercase tracking-widest text-muted-foreground">Client Tools</p>
+          <p className="text-[11px] text-muted-foreground">滑块控制调试会话内客户端工具是否启用。</p>
+          <div className="space-y-2">
+            {DEBUG_CLIENT_TOOLS.map((tool) => {
+              const enabled = isClientToolEnabled(tool.id);
+              return (
+                <div key={tool.id} className="flex items-center justify-between gap-3 rounded-md border border-white/10 bg-black/20 px-2 py-1.5">
+                  <div className="min-w-0">
+                    <div className="text-[11px] font-mono text-foreground truncate">{tool.name}</div>
+                    <div className="text-[10px] text-muted-foreground truncate">{tool.description}</div>
+                  </div>
+                  <button
+                    type="button"
+                    onClick={() => setClientToolEnabledMap((prev) => ({ ...prev, [tool.id]: !enabled }))}
+                    className={`relative h-6 w-11 rounded-full transition-colors ${enabled ? 'bg-emerald-500/80' : 'bg-white/20'}`}
+                    title={enabled ? '点击关闭' : '点击开启'}
+                  >
+                    <span
+                      className={`absolute top-0.5 h-5 w-5 rounded-full bg-white shadow transition-transform ${enabled ? 'translate-x-5' : 'translate-x-0.5'}`}
+                    />
+                  </button>
+                </div>
+              );
+            })}
+          </div>
+        </div>
         <div className="rounded-md border border-white/10 bg-black/20 p-2 space-y-2">
           <div className="flex items-center justify-between gap-2">
             <p className="text-[10px] uppercase tracking-widest text-muted-foreground">Dynamic Variables</p>