diff --git a/app/canvas/[id]/page.tsx b/app/canvas/[id]/page.tsx
index 02658ed1f..911ee17fb 100644
--- a/app/canvas/[id]/page.tsx
+++ b/app/canvas/[id]/page.tsx
@@ -347,6 +347,7 @@ export default function CanvasEditorPage({ params }: PageProps) {
   const [agentProjectDeletedResultCollections, setAgentProjectDeletedResultCollections] =
     useState<AgentGenerationProjectResultCollections>({});
   const [isAgentProjectLoading, setIsAgentProjectLoading] = useState(false);
+  const [loadedAgentProjectId, setLoadedAgentProjectId] = useState<string | null>(null);
   const [isAgentProjectSaving, setIsAgentProjectSaving] = useState(false);
   const [isAgentProjectSheetOpen, setIsAgentProjectSheetOpen] = useState(false);
   const [isAgentProjectMenuOpen, setIsAgentProjectMenuOpen] = useState(false);
@@ -408,6 +409,8 @@ export default function CanvasEditorPage({ params }: PageProps) {
   const isCanvasAgentModeEnabled = siteSettingsData?.canvasAgentModeEnabled !== false;
   const isAgentMode =
     isAgentWorkspaceEnabled && requestedAgentMode;
+  const hasLoadedCurrentAgentProject =
+    !requestedAgentMode || !agentProjectId || loadedAgentProjectId === agentProjectId;
   const resolvedBrandModelConfig = useMemo(
     () => normalizeAgentWorkflowBrandModelConfig(siteSettingsData?.agentWorkflowBrandModelConfig),
     [siteSettingsData?.agentWorkflowBrandModelConfig]
@@ -526,6 +529,7 @@ export default function CanvasEditorPage({ params }: PageProps) {
       setAgentProjectThumbnail(null);
       setAgentProjectResultCollections({});
       setAgentProjectDeletedResultCollections({});
+      setLoadedAgentProjectId(null);
       
       // 🆕 先清空当前画布状态，确保切换时不会显示旧数据
       useCanvasStore.getState().clearCanvas();
@@ -886,6 +890,7 @@ export default function CanvasEditorPage({ params }: PageProps) {
     const loadAgentProject = async () => {
       setIsAgentProjectMenuOpen(false);
       setIsAgentProjectLoading(true);
+      setLoadedAgentProjectId(null);
       try {
         const result = await agentProjectService.getProject(agentProjectId);
         if (!result.success || !result.data) {
@@ -921,6 +926,7 @@ export default function CanvasEditorPage({ params }: PageProps) {
         setAgentProjectDeletedResultCollections(
           persistedState.deletedResultCollections || {}
         );
+        setLoadedAgentProjectId(agentProjectId);
       } catch (error) {
         if (!cancelled) {
           toast.error(error instanceof Error ? error.message : "加载生图项目失败");
@@ -945,7 +951,14 @@ export default function CanvasEditorPage({ params }: PageProps) {
   }, [isAgentProjectSheetOpen]);
 
   useEffect(() => {
-    if (!isAgentMode || !agentProjectId || isAgentProjectLoading) return;
+    if (
+      !isAgentMode ||
+      !agentProjectId ||
+      isAgentProjectLoading ||
+      !hasLoadedCurrentAgentProject
+    ) {
+      return;
+    }
 
     const timer = window.setTimeout(async () => {
       setIsAgentProjectSaving(true);
@@ -967,6 +980,7 @@ export default function CanvasEditorPage({ params }: PageProps) {
     currentAgentStage,
     isAgentMode,
     isAgentProjectLoading,
+    hasLoadedCurrentAgentProject,
     persistAgentProject,
     selectedAgentPresetId,
     selectedBrandModel,
diff --git a/components/agents/AgentGenerationWorkspaceDarkV2.tsx b/components/agents/AgentGenerationWorkspaceDarkV2.tsx
index 8ab6e3bf0..58a89efb4 100644
--- a/components/agents/AgentGenerationWorkspaceDarkV2.tsx
+++ b/components/agents/AgentGenerationWorkspaceDarkV2.tsx
@@ -1053,8 +1053,6 @@ export function AgentGenerationWorkspaceDarkV2({
     detailReplacementState.method === "ai_detail_generate"
       ? "ai_detail_generate"
       : "reference_replace";
-  const isDetailAiGenerationMethod =
-    Boolean(selectedAgentPresetId) && detailReplacementMethod === "ai_detail_generate";
   const presetModeConfig = useMemo(
     () => normalizeAgentPresetModeConfig(selectedAgentPreset?.defaultParams),
     [selectedAgentPreset?.defaultParams]
@@ -1065,6 +1063,8 @@ export function AgentGenerationWorkspaceDarkV2({
     selectedAgentPreset?.type === "image" && presetModeConfig.modeType === "detail_replacement";
   const isSkuReplacementPreset =
     selectedAgentPreset?.type === "image" && presetModeConfig.modeType === "sku_replacement";
+  const isDetailAiGenerationMethod =
+    isDetailReplacementPreset && detailReplacementMethod === "ai_detail_generate";
   const isReplacementPreset =
     (isDetailReplacementPreset && !isDetailAiGenerationMethod) || isSkuReplacementPreset;
   const currentResultModeType: AgentGenerationResultModeType =
diff --git a/components/agents/AgentProjectListSheet.tsx b/components/agents/AgentProjectListSheet.tsx
index 338fb5d9a..90d85e32f 100644
--- a/components/agents/AgentProjectListSheet.tsx
+++ b/components/agents/AgentProjectListSheet.tsx
@@ -19,6 +19,23 @@ import { cn } from "@/lib/utils";
 import { buildImageProxyUrl } from "@/lib/image-delivery";
 import type { AgentGenerationProject } from "@/types/agent";
 
+function getProjectPreviewUrl(project: AgentGenerationProject) {
+  const explicitThumbnail = String(project.thumbnail || "").trim();
+  if (explicitThumbnail) {
+    return explicitThumbnail;
+  }
+
+  const resultCollections = project.projectState?.resultCollections;
+  const fallbackUrl =
+    resultCollections?.scene_generation?.[0] ||
+    resultCollections?.detail_generation?.[0] ||
+    resultCollections?.detail_replacement?.[0] ||
+    resultCollections?.sku_replacement?.[0] ||
+    "";
+
+  return String(fallbackUrl || "").trim() || null;
+}
+
 interface AgentProjectListSheetProps {
   open: boolean;
   onOpenChange: (open: boolean) => void;
@@ -98,7 +115,10 @@ export function AgentProjectListSheet({
                 <Loader2 className="h-6 w-6 animate-spin text-white/50" />
               </div>
             ) : projects.length > 0 ? (
-              projects.map((project) => (
+              projects.map((project) => {
+                const previewUrl = getProjectPreviewUrl(project);
+
+                return (
                 <button
                   key={project.id}
                   type="button"
@@ -114,9 +134,9 @@ export function AgentProjectListSheet({
                   )}
                 >
                   <div className="h-14 w-14 shrink-0 overflow-hidden rounded-xl border border-white/10 bg-black/30">
-                    {project.thumbnail ? (
+                    {previewUrl ? (
                       <img
-                        src={buildImageProxyUrl(project.thumbnail, {
+                        src={buildImageProxyUrl(previewUrl, {
                           width: 160,
                           quality: 82,
                           format: "webp",
@@ -197,7 +217,8 @@ export function AgentProjectListSheet({
                     )}
                   </Button>
                 </button>
-              ))
+                );
+              })
             ) : (
               <div className="rounded-2xl border border-dashed border-white/10 bg-white/[0.02] px-4 py-12 text-center">
                 <div className="text-sm text-white/70">还没有生图项目</div>