diff --git a/app/(chat)/api/chat/route.ts b/app/(chat)/api/chat/route.ts
index 769de525a..5c3f8a432 100644
--- a/app/(chat)/api/chat/route.ts
+++ b/app/(chat)/api/chat/route.ts
@@ -251,6 +251,17 @@ function startStreamKeepalive(writer: StreamWriter, label: string, intervalMs =
 
 type VideoModeType = "text-to-video" | "first-frame" | "first-last-frame" | "reference-images";
 
+const VIDEO_PROVIDER_TYPES = new Set([
+  "volcano-video",
+  "doubao-video",
+  "qianwen-video",
+  "fal-video",
+]);
+
+function isVideoProviderType(providerType?: string | null): boolean {
+  return Boolean(providerType && VIDEO_PROVIDER_TYPES.has(providerType));
+}
+
 function inferSupportedVideoModesByModelId(modelId: string): VideoModeType[] {
   const normalized = modelId.toLowerCase();
 
@@ -1438,6 +1449,7 @@ export async function POST(request: Request) {
     // 🆕 存储智能模式的相关信息
     let smartAutoFriendlyMessage: string | undefined;  // AI的自然对话回复
     let smartAutoOptimizedPrompt: string | undefined;  // 优化后的提示词（不修改用户消息，只用于API调用）
+    let smartAutoPromptFromVideoPlan = false;
     let smartAutoRecommendedImageParams: AgentRecommendedImageParams | undefined;
     let smartAutoVideoPlan: AgentVideoPlan | undefined;
     let smartAutoRecommendedVideoParams: AgentRecommendedVideoParams | undefined;
@@ -1448,6 +1460,7 @@ export async function POST(request: Request) {
     let shouldRunAgentConversation = finalModelId === "auto";
     let shouldKeepSelectedModel = false;
     const requestedModelId = selectedChatModel;
+    let requestedModelProviderType: string | undefined;
 
     if (!shouldRunAgentConversation && requestedModelId !== "auto") {
       const selectedModelIsUUID =
@@ -1475,6 +1488,8 @@ export async function POST(request: Request) {
         selectedModelProviderType = selectedProvider?.type as string | undefined;
       }
 
+      requestedModelProviderType = selectedModelProviderType;
+
       if (selectedModelConfig) {
         const fixedImageProviderTypes = new Set([
           "gemini",
@@ -1484,17 +1499,11 @@ export async function POST(request: Request) {
           "fal-image",
           "volcano-vision",
         ]);
-        const fixedVideoProviderTypes = new Set([
-          "volcano-video",
-          "doubao-video",
-          "qianwen-video",
-          "fal-video",
-        ]);
         const isFixedVisualModel =
           !selectedModelConfig.isSubModel &&
           (selectedModelConfig.supportsImageGen ||
             (selectedModelProviderType
-              ? fixedVideoProviderTypes.has(selectedModelProviderType)
+              ? isVideoProviderType(selectedModelProviderType)
               : false) ||
             (selectedModelProviderType
               ? fixedImageProviderTypes.has(selectedModelProviderType)
@@ -1516,6 +1525,9 @@ export async function POST(request: Request) {
       }
     }
 
+    const allowAgentVideoGeneration =
+      Boolean(requestBody.videoParams) || isVideoProviderType(requestedModelProviderType);
+
     // ========== Smart Auto Mode Logic ==========
     if (shouldRunAgentConversation) {
       console.log("[Smart Auto Mode] 🚀 Starting intelligent analysis...");
@@ -1770,6 +1782,7 @@ export async function POST(request: Request) {
           smartAutoRecommendedVideoParams = autoGraphResult.videoPlan.recommendedVideoParams;
           if (!smartAutoOptimizedPrompt && autoGraphResult.videoPlan.finalPrompt?.trim()) {
             smartAutoOptimizedPrompt = autoGraphResult.videoPlan.finalPrompt.trim();
+            smartAutoPromptFromVideoPlan = true;
           }
           console.log("[Smart Auto Mode] 🎬 Agent video plan ready:", {
             hasScript: Boolean(autoGraphResult.videoPlan.script),
@@ -1784,8 +1797,49 @@ export async function POST(request: Request) {
         }
 
         if (autoGraphResult.route && !shouldKeepSelectedModel) {
-          finalModelId = autoGraphResult.route.id;
-          console.log(`[Smart Auto Mode] ✅ Routed to: ${autoGraphResult.route.displayName} (${autoGraphResult.route.reason})`);
+          const routeIsVideo = isVideoProviderType(autoGraphResult.route.providerType);
+          if (routeIsVideo && !allowAgentVideoGeneration) {
+            const fallbackIntent: "image_edit" | "image_gen" = hasImage ? "image_edit" : "image_gen";
+            smartAutoDetectedIntent = fallbackIntent;
+            smartAutoVideoPlan = undefined;
+            smartAutoRecommendedVideoParams = undefined;
+            if (smartAutoPromptFromVideoPlan) {
+              smartAutoOptimizedPrompt = textContent.trim() || undefined;
+              smartAutoPromptFromVideoPlan = false;
+            }
+            smartAutoFriendlyMessage =
+              smartAutoFriendlyMessage && !/视频/.test(smartAutoFriendlyMessage)
+                ? smartAutoFriendlyMessage
+                : "当前 Agent 默认按图片任务执行；如需生成视频，请先手动切换到“视频”模式。";
+            console.log(
+              `[Smart Auto Mode] 🚫 Blocked auto video route (${autoGraphResult.route.displayName}), fallback to ${fallbackIntent}`,
+            );
+            try {
+              const { routeToModel } = await import("@/lib/ai/model-router");
+              const fallbackRoute = await routeToModel({
+                intent: fallbackIntent,
+                subIntent: autoGraphResult.analysis?.subIntent,
+                hasImage,
+              });
+              if (!isVideoProviderType(fallbackRoute.providerType)) {
+                finalModelId = fallbackRoute.id;
+                console.log(
+                  `[Smart Auto Mode] ✅ Fallback routed to: ${fallbackRoute.displayName} (${fallbackRoute.reason})`,
+                );
+              } else {
+                console.warn(
+                  `[Smart Auto Mode] ⚠️ Fallback route still video (${fallbackRoute.displayName}), keep previous model`,
+                );
+              }
+            } catch (fallbackRouteError) {
+              console.error("[Smart Auto Mode] Failed to resolve non-video fallback route:", fallbackRouteError);
+            }
+          } else {
+            finalModelId = autoGraphResult.route.id;
+            console.log(
+              `[Smart Auto Mode] ✅ Routed to: ${autoGraphResult.route.displayName} (${autoGraphResult.route.reason})`,
+            );
+          }
         } else if (autoGraphResult.route && shouldKeepSelectedModel) {
           finalModelId = requestedModelId;
           console.log("[Smart Auto Mode] 🔒 Keep user-selected model, skip routing override");
@@ -1943,6 +1997,7 @@ export async function POST(request: Request) {
     const shouldApplyAgentVideoParams =
       shouldRunAgentConversation &&
       !smartAutoNeedsClarification &&
+      allowAgentVideoGeneration &&
       smartAutoDetectedIntent === "video_gen";
     const effectiveImageParams = shouldApplyAgentImageParams
       ? mergeImageParamsWithAgentRecommendation({
@@ -3528,9 +3583,14 @@ export async function POST(request: Request) {
           });
           activeTools.push("requestSuggestions");
         }
-        if (enabledTools.includes("generateVideo")) {
+        const shouldEnableGenerateVideoTool =
+          enabledTools.includes("generateVideo") &&
+          (!shouldRunAgentConversation || allowAgentVideoGeneration);
+        if (shouldEnableGenerateVideoTool) {
           tools.generateVideo = generateVideo({ dataStream });
           activeTools.push("generateVideo");
+        } else if (enabledTools.includes("generateVideo") && shouldRunAgentConversation) {
+          console.log("[Smart Auto Mode] 🚫 generateVideo tool disabled (manual video mode not selected)");
         }
 
         console.log("[Chat API] Calling streamText with model:", (languageModel as any).modelId, (languageModel as any).provider); // 调试日志