Enhance conversation history and runtime variable management

- Update ConversationRecorder to include source and nodeId metadata in transcripts for better context tracking.
- Introduce optional variable handling in DynamicVariableStore, allowing for unset variables to be rendered as empty without raising errors.
- Refactor WorkflowBrain to apply turn configurations and manage interaction policies dynamically, improving agent responsiveness.
- Implement tests to ensure proper handling of updated session variables and workflow metadata in various scenarios.

frontend/src/components/pages/AssistantPage.tsx

@@ -122,6 +122,10 @@ import {
   defaultGraph,
   type WorkflowGraph,
 } from "@/components/workflow/specs";
+import {
+  defaultTurnConfig,
+  normalizeTurnConfig,
+} from "@/lib/turn-config";
 
 type RuntimeMode = "pipeline" | "realtime";
 
@@ -185,24 +189,6 @@ const assistantTypes: AssistantType[] = [
   "OpenCode",
 ];
 
-function defaultTurnConfig(): TurnConfig {
-  return {
-    bargeIn: {
-      strategy: "vad",
-    },
-    vad: {
-      confidence: 0.7,
-      startSecs: 0.2,
-      stopSecs: 0.2,
-      minVolume: 0.6,
-    },
-    turnDetection: {
-      strategy: "silence",
-      silenceTimeoutSecs: 0.6,
-    },
-  };
-}
-
 function defaultKnowledgeRetrievalConfig(): KnowledgeRetrievalConfig {
   return {
     mode: "automatic",
@@ -305,6 +291,45 @@ function activeDynamicVariableDefinitions(
   );
 }
 
+function activeWorkflowDynamicVariableDefinitions(
+  graph: WorkflowGraph,
+  saved: Record<string, DynamicVariableDefinition>,
+): Record<string, DynamicVariableDefinition> {
+  const names = new Set(extractDynamicVariableNames(JSON.stringify(graph)));
+
+  // Expression operands and Action assignment destinations are variable
+  // references even though they do not use the {{placeholder}} syntax.
+  for (const edge of graph.edges) {
+    for (const rule of edge.data.expression?.rules ?? []) {
+      if (isPublicDynamicVariableName(rule.variable)) names.add(rule.variable);
+    }
+  }
+  for (const node of graph.nodes) {
+    for (const name of Object.keys(node.data.resultAssignments ?? {})) {
+      if (isPublicDynamicVariableName(name)) names.add(name);
+    }
+  }
+
+  return Object.fromEntries(
+    [...names].sort().map((name) => [
+      name,
+      saved[name] ?? {
+        type: "string",
+        required: false,
+        default: null,
+      },
+    ]),
+  );
+}
+
+function isPublicDynamicVariableName(name: string): boolean {
+  return (
+    /^[A-Za-z][A-Za-z0-9_]{0,63}$/.test(name) &&
+    !name.startsWith("system__") &&
+    !name.startsWith("secret__")
+  );
+}
+
 function blankFastGptForm(name: string): FastGptForm {
   return {
     name,
@@ -492,6 +517,11 @@ export function AssistantPage(props: AssistantPageProps) {
     [form.prompt, form.greeting],
     form.dynamicVariableDefinitions,
   );
+  const effectiveWorkflowDynamicVariableDefinitions =
+    activeWorkflowDynamicVariableDefinitions(
+      workflowGraph,
+      workflowDynamicVariableDefinitions,
+    );
 
   const loadAssistants = useCallback(async () => {
     setListLoading(true);
@@ -603,7 +633,7 @@ export function AssistantPage(props: AssistantPageProps) {
       knowledgeRetrievalConfig:
         a.knowledgeRetrievalConfig ?? defaultKnowledgeRetrievalConfig(),
       enableInterrupt: a.enableInterrupt,
-      turnConfig: a.turnConfig,
+      turnConfig: normalizeTurnConfig(a.turnConfig),
       visionEnabled: a.visionEnabled,
       visionModelResourceId: a.visionModelResourceId ?? "",
       toolIds: a.toolIds ?? [],
@@ -711,7 +741,7 @@ export function AssistantPage(props: AssistantPageProps) {
             name: workflowName,
             graph: workflowGraph,
             settings: workflowSettings,
-            dynamicVariableDefinitions: workflowDynamicVariableDefinitions,
+            dynamicVariableDefinitions: effectiveWorkflowDynamicVariableDefinitions,
           }),
         );
       }
@@ -756,7 +786,7 @@ export function AssistantPage(props: AssistantPageProps) {
       asr: a.modelResourceIds.ASR ?? "",
       voice: a.modelResourceIds.TTS ?? "",
       enableInterrupt: a.enableInterrupt,
-      turnConfig: a.turnConfig,
+      turnConfig: normalizeTurnConfig(a.turnConfig),
     };
     setDifyForm(next);
     return next;
@@ -786,7 +816,7 @@ export function AssistantPage(props: AssistantPageProps) {
       asr: a.modelResourceIds.ASR ?? "",
       voice: a.modelResourceIds.TTS ?? "",
       enableInterrupt: a.enableInterrupt,
-      turnConfig: a.turnConfig,
+      turnConfig: normalizeTurnConfig(a.turnConfig),
     };
     setFastGptForm(next);
     return next;
@@ -818,7 +848,7 @@ export function AssistantPage(props: AssistantPageProps) {
       asr: a.modelResourceIds.ASR ?? "",
       voice: a.modelResourceIds.TTS ?? "",
       enableInterrupt: a.enableInterrupt,
-      turnConfig: a.turnConfig,
+      turnConfig: normalizeTurnConfig(a.turnConfig),
       visionEnabled: a.visionEnabled,
       visionModelResourceId: a.visionModelResourceId ?? "",
     };
@@ -872,21 +902,29 @@ export function AssistantPage(props: AssistantPageProps) {
                 assistant.knowledgeRetrievalConfig.scoreThreshold,
             },
             globalPrompt: graph.settings?.globalPrompt ?? "",
-            allowInterrupt: assistant.enableInterrupt,
-            turnConfig: assistant.turnConfig,
+            allowInterrupt:
+              graph.settings?.enableInterrupt ?? assistant.enableInterrupt,
+            turnConfig: normalizeTurnConfig(
+              graph.settings?.turnConfig ?? assistant.turnConfig,
+            ),
           };
           setWorkflowName(assistant.name);
           setWorkflowGraph(graph);
           setWorkflowSettings(wfSettings);
+          const dynamicVariableDefinitions =
+            activeWorkflowDynamicVariableDefinitions(
+              graph,
+              assistant.dynamicVariableDefinitions ?? {},
+            );
           setWorkflowDynamicVariableDefinitions(
-            assistant.dynamicVariableDefinitions ?? {},
+            dynamicVariableDefinitions,
           );
           setSavedSnapshot(
             JSON.stringify({
               name: assistant.name,
               graph,
               settings: wfSettings,
-              dynamicVariableDefinitions: assistant.dynamicVariableDefinitions ?? {},
+              dynamicVariableDefinitions,
             }),
           );
         }
@@ -941,7 +979,7 @@ export function AssistantPage(props: AssistantPageProps) {
         knowledgeRetrievalConfig: workflowSettings.knowledgeRetrievalConfig,
         toolIds: workflowSettings.toolIds,
         graph: workflowGraph as unknown as Record<string, unknown>,
-        dynamicVariableDefinitions: workflowDynamicVariableDefinitions,
+        dynamicVariableDefinitions: effectiveWorkflowDynamicVariableDefinitions,
       }),
     );
   }
@@ -961,7 +999,8 @@ export function AssistantPage(props: AssistantPageProps) {
                   name: workflowName,
                   graph: workflowGraph,
                   settings: workflowSettings,
-                  dynamicVariableDefinitions: workflowDynamicVariableDefinitions,
+                  dynamicVariableDefinitions:
+                    effectiveWorkflowDynamicVariableDefinitions,
                 })
               : null;
   const dirty =
@@ -1473,7 +1512,9 @@ export function AssistantPage(props: AssistantPageProps) {
                 hasUnsavedChanges={dirty}
                 onNodeActive={setActiveNodeId}
                 dynamicVariablesEnabled
-                dynamicVariableDefinitions={workflowDynamicVariableDefinitions}
+                dynamicVariableDefinitions={
+                  effectiveWorkflowDynamicVariableDefinitions
+                }
               />
             }
             activeNodeId={activeNodeId}
@@ -1492,7 +1533,7 @@ export function AssistantPage(props: AssistantPageProps) {
         <DynamicVariablesDialog
           open={dynamicVariablesOpen}
           onOpenChange={setDynamicVariablesOpen}
-          definitions={workflowDynamicVariableDefinitions}
+          definitions={effectiveWorkflowDynamicVariableDefinitions}
           onChange={setWorkflowDynamicVariableDefinitions}
         />
       </div>
@@ -1872,80 +1913,6 @@ export function AssistantPage(props: AssistantPageProps) {
 
       <div className="flex min-h-0 flex-1 gap-4">
         <div className="scrollbar-subtle min-w-0 flex-1 space-y-3 overflow-y-auto pr-1">
-          <SectionCard>
-            <div className="grid grid-cols-1 gap-3 md:grid-cols-2">
-              <div
-                role="button"
-                tabIndex={0}
-                onClick={() => updateForm("runtimeMode", "pipeline")}
-                onKeyDown={(event) => {
-                  if (event.key === "Enter" || event.key === " ") {
-                    event.preventDefault();
-                    updateForm("runtimeMode", "pipeline");
-                  }
-                }}
-                className={[
-                  "cursor-pointer rounded-xl border p-3.5 text-left transition-colors",
-                  form.runtimeMode === "pipeline"
-                    ? "border-primary bg-primary/5 ring-1 ring-primary"
-                    : "border-hairline bg-canvas-soft hover:border-hairline-strong",
-                ].join(" ")}
-              >
-                <div className="flex items-center justify-between gap-3">
-                  <div className="flex items-center gap-2.5">
-                    <div className="flex h-8 w-8 shrink-0 items-center justify-center rounded-full bg-surface-strong text-foreground">
-                      <Waypoints size={15} />
-                    </div>
-                    <div className="flex items-center gap-1.5">
-                      <span className="text-sm font-medium text-foreground">Pipeline 模式</span>
-                      <HelpHint text="通过 ASR、LLM 和 TTS 级联组成语音管线，灵活选配各模块。" />
-                    </div>
-                  </div>
-                  {form.runtimeMode === "pipeline" && (
-                    <span className="flex h-5 w-5 shrink-0 items-center justify-center rounded-full bg-primary text-primary-foreground">
-                      <Check size={12} />
-                    </span>
-                  )}
-                </div>
-              </div>
-
-              <div
-                role="button"
-                tabIndex={0}
-                onClick={() => updateForm("runtimeMode", "realtime")}
-                onKeyDown={(event) => {
-                  if (event.key === "Enter" || event.key === " ") {
-                    event.preventDefault();
-                    updateForm("runtimeMode", "realtime");
-                  }
-                }}
-                className={[
-                  "cursor-pointer rounded-xl border p-3.5 text-left transition-colors",
-                  form.runtimeMode === "realtime"
-                    ? "border-primary bg-primary/5 ring-1 ring-primary"
-                    : "border-hairline bg-canvas-soft hover:border-hairline-strong",
-                ].join(" ")}
-              >
-                <div className="flex items-center justify-between gap-3">
-                  <div className="flex items-center gap-2.5">
-                    <div className="flex h-8 w-8 shrink-0 items-center justify-center rounded-full bg-surface-strong text-foreground">
-                      <AudioLines size={15} />
-                    </div>
-                    <div className="flex items-center gap-1.5">
-                      <span className="text-sm font-medium text-foreground">Realtime 模式</span>
-                      <HelpHint text="使用原生实时语音模型，模型直接处理音频输入并生成语音回复。" />
-                    </div>
-                  </div>
-                  {form.runtimeMode === "realtime" && (
-                    <span className="flex h-5 w-5 shrink-0 items-center justify-center rounded-full bg-primary text-primary-foreground">
-                      <Check size={12} />
-                    </span>
-                  )}
-                </div>
-              </div>
-            </div>
-          </SectionCard>
-
           <SectionCard
             icon={<MessageSquareText size={15} />}
             title="提示词"
@@ -1963,12 +1930,38 @@ export function AssistantPage(props: AssistantPageProps) {
             />
           </SectionCard>
 
-          {form.runtimeMode === "pipeline" ? (
-            <SectionCard
-              icon={<Brain size={15} />}
-              title="模型配置"
-              description="从「模型资源」中选择大语言模型、语音识别与语音合成"
-            >
+          <SectionCard
+            icon={<Bot size={15} />}
+            title="开场白"
+            description="助手与用户首次对话时的开场语"
+          >
+            <TextAreaField
+              value={form.greeting}
+              onChange={(value) => updateForm("greeting", value)}
+              placeholder="请输入助手开场白"
+            />
+            <DynamicVariableEditorHint
+              count={Object.keys(effectiveDynamicVariableDefinitions).length}
+              onOpen={() => setDynamicVariablesOpen(true)}
+            />
+          </SectionCard>
+
+          <SectionCard
+            icon={<Brain size={15} />}
+            title="模型配置"
+            description={
+              form.runtimeMode === "pipeline"
+                ? "选择运行方式，以及大语言模型、语音识别与语音合成资源"
+                : "选择运行方式；Realtime 模型内置语音识别与语音合成"
+            }
+          >
+            <RuntimeModeSelector
+              value={form.runtimeMode}
+              onChange={(runtimeMode) => updateForm("runtimeMode", runtimeMode)}
+            />
+
+            {form.runtimeMode === "pipeline" ? (
+              <>
               <ToggleRow
                 title="视觉理解"
                 hint="开启后，开始对话时会允许助手按需理解当前视频画面。视觉模型选「模型自己」时，大语言模型本身必须支持图片输入。"
@@ -2007,13 +2000,8 @@ export function AssistantPage(props: AssistantPageProps) {
                 options={credOptions("TTS")}
                 noneLabel="无"
               />
-            </SectionCard>
-          ) : (
-            <SectionCard
-              icon={<Brain size={15} />}
-              title="模型配置"
-              description="当前模式下 ASR 与 TTS 由 Realtime 模型内置完成"
-            >
+              </>
+            ) : (
               <ResourceSelectField
                 label="Realtime 模型"
                 value={form.realtimeModel}
@@ -2021,23 +2009,7 @@ export function AssistantPage(props: AssistantPageProps) {
                 options={credOptions("Realtime")}
                 noneLabel="无"
               />
-            </SectionCard>
-          )}
-
-          <SectionCard
-            icon={<Bot size={15} />}
-            title="开场白"
-            description="助手与用户首次对话时的开场语"
-          >
-            <TextAreaField
-              value={form.greeting}
-              onChange={(value) => updateForm("greeting", value)}
-              placeholder="请输入助手开场白"
-            />
-            <DynamicVariableEditorHint
-              count={Object.keys(effectiveDynamicVariableDefinitions).length}
-              onOpen={() => setDynamicVariablesOpen(true)}
-            />
+            )}
           </SectionCard>
 
           {form.runtimeMode === "pipeline" && (
@@ -2206,10 +2178,23 @@ function DebugDrawer({
   >({});
   const recording =
     preview.status === "connecting" || preview.status === "connected";
-  const dynamicVariableEntries = Object.entries(dynamicVariableDefinitions);
+  const displayedDefinitions = { ...dynamicVariableDefinitions };
+  for (const [name, value] of Object.entries(preview.sessionVariables)) {
+    displayedDefinitions[name] ??= {
+      type:
+        typeof value === "number"
+          ? "number"
+          : typeof value === "boolean"
+            ? "boolean"
+            : "string",
+      required: false,
+      default: null,
+    };
+  }
+  const dynamicVariableEntries = Object.entries(displayedDefinitions);
   const resolvedDynamicVariables: Record<string, string | number | boolean> = {};
   let dynamicVariablesError = "";
-  for (const [name, definition] of dynamicVariableEntries) {
+  for (const [name, definition] of Object.entries(dynamicVariableDefinitions)) {
     const value = dynamicVariableValues[name] ?? definition.default;
     if (value === null || value === undefined || value === "") {
       if (definition.required && !dynamicVariablesError) {
@@ -2265,7 +2250,8 @@ function DebugDrawer({
             <DynamicVariableValuesPopover
               entries={dynamicVariableEntries}
               values={dynamicVariableValues}
-              disabled={recording}
+              sessionValues={preview.sessionVariables}
+              readOnly={recording}
               onChange={setDynamicVariableValues}
             />
           )}
@@ -2330,12 +2316,14 @@ function DebugDrawer({
 function DynamicVariableValuesPopover({
   entries,
   values,
-  disabled,
+  sessionValues,
+  readOnly,
   onChange,
 }: {
   entries: [string, DynamicVariableDefinition][];
   values: Record<string, string | number | boolean>;
-  disabled: boolean;
+  sessionValues: Record<string, string | number | boolean>;
+  readOnly: boolean;
   onChange: React.Dispatch<
     React.SetStateAction<Record<string, string | number | boolean>>
   >;
@@ -2354,10 +2342,9 @@ function DynamicVariableValuesPopover({
       <PopoverTrigger asChild>
         <button
           type="button"
-          disabled={disabled}
-          aria-label="设置本次会话变量"
-          title="本次会话变量"
-          className="relative flex h-8 w-8 items-center justify-center rounded-full border border-hairline bg-canvas-soft text-muted-foreground transition-colors hover:bg-surface-strong hover:text-foreground disabled:cursor-not-allowed disabled:opacity-40"
+          aria-label={readOnly ? "查看本次会话变量" : "设置本次会话变量"}
+          title={readOnly ? "查看实时会话变量" : "本次会话变量"}
+          className="relative flex h-8 w-8 items-center justify-center rounded-full border border-hairline bg-canvas-soft text-muted-foreground transition-colors hover:bg-surface-strong hover:text-foreground"
         >
           <Braces size={15} />
           <span className="absolute -right-1 -top-1 flex h-4 min-w-4 items-center justify-center rounded-full border border-card bg-surface-strong px-1 text-[9px] tabular-nums text-foreground">
@@ -2376,7 +2363,9 @@ function DynamicVariableValuesPopover({
             本次会话变量
           </div>
           <p className="text-xs leading-5 text-muted-foreground">
-            这些值只用于下一次调试会话，不会修改助手配置。
+            {readOnly
+              ? "当前值会在 Action 或工具更新变量后实时刷新。"
+              : "这些值只用于下一次调试会话，不会修改助手配置。"}
           </p>
         </div>
         <div className="max-h-72 space-y-3 overflow-y-auto pr-1">
@@ -2386,11 +2375,14 @@ function DynamicVariableValuesPopover({
                 当前没有会话变量
               </div>
               <p className="mt-1 text-[11px] leading-5 text-muted-foreground">
-                在提示词或开场白中添加 {"{{variable_name}}"} 后，可在这里设置调试值。
+                在工作流提示词、节点话术、边条件或 Action 中引用变量后，
+                可在这里设置调试值。
               </p>
             </div>
           ) : entries.map(([name, definition]) => {
-            const value = values[name] ?? definition.default ?? "";
+            const value = readOnly
+              ? sessionValues[name] ?? definition.default ?? ""
+              : values[name] ?? definition.default ?? "";
             return (
               <label key={name} className="block space-y-1.5">
                 <span className="flex items-center gap-1.5 text-xs font-medium text-foreground">
@@ -2408,6 +2400,7 @@ function DynamicVariableValuesPopover({
                 </span>
                 {definition.type === "boolean" ? (
                   <Select
+                    disabled={readOnly}
                     value={value === "" ? "unset" : String(value)}
                     onValueChange={(next) =>
                       setValue(
@@ -2430,6 +2423,7 @@ function DynamicVariableValuesPopover({
                   </Select>
                 ) : (
                   <Input
+                    disabled={readOnly}
                     type={definition.type === "number" ? "number" : "text"}
                     value={typeof value === "boolean" ? String(value) : value}
                     onChange={(event) => {
@@ -3465,7 +3459,7 @@ function DynamicVariablesDialog({
             动态变量
           </DialogTitle>
           <DialogDescription className="text-xs leading-5">
-            提示词和开场白中使用的自定义变量会自动出现在这里。
+            助手配置中引用的自定义变量会自动出现在这里。
           </DialogDescription>
         </DialogHeader>
 
@@ -3493,7 +3487,7 @@ function DynamicVariablesDialog({
               <div className="rounded-xl border border-dashed border-hairline-strong bg-canvas-soft px-4 py-5 text-center">
                 <div className="text-sm font-medium text-foreground">还没有自定义变量</div>
                 <p className="mt-1 text-xs leading-5 text-muted-foreground">
-                  在提示词或开场白中输入 {"{{customer_name}}"} 即可添加。
+                  在提示词或节点话术中输入 {"{{customer_name}}"} 即可添加。
                 </p>
               </div>
             ) : (
@@ -3661,6 +3655,78 @@ function DynamicVariablesDialog({
   );
 }
 
+function RuntimeModeSelector({
+  value,
+  onChange,
+}: {
+  value: RuntimeMode;
+  onChange: (mode: RuntimeMode) => void;
+}) {
+  const options = [
+    {
+      value: "pipeline" as const,
+      label: "Pipeline 模式",
+      hint: "通过 ASR、LLM 和 TTS 级联组成语音管线，灵活选配各模块。",
+      icon: Waypoints,
+    },
+    {
+      value: "realtime" as const,
+      label: "Realtime 模式",
+      hint: "使用原生实时语音模型，模型直接处理音频输入并生成语音回复。",
+      icon: AudioLines,
+    },
+  ];
+
+  return (
+    <div className="grid grid-cols-1 gap-3 border-b border-hairline-soft pb-4 md:grid-cols-2">
+      {options.map((option) => {
+        const Icon = option.icon;
+        const selected = value === option.value;
+        const select = () => onChange(option.value);
+        return (
+          <div
+            key={option.value}
+            role="button"
+            tabIndex={0}
+            onClick={select}
+            onKeyDown={(event) => {
+              if (event.key === "Enter" || event.key === " ") {
+                event.preventDefault();
+                select();
+              }
+            }}
+            className={[
+              "cursor-pointer rounded-xl border p-3.5 text-left transition-colors",
+              selected
+                ? "border-primary bg-primary/5 ring-1 ring-primary"
+                : "border-hairline bg-canvas-soft hover:border-hairline-strong",
+            ].join(" ")}
+          >
+            <div className="flex items-center justify-between gap-3">
+              <div className="flex items-center gap-2.5">
+                <div className="flex h-8 w-8 shrink-0 items-center justify-center rounded-full bg-surface-strong text-foreground">
+                  <Icon size={15} />
+                </div>
+                <div className="flex items-center gap-1.5">
+                  <span className="text-sm font-medium text-foreground">
+                    {option.label}
+                  </span>
+                  <HelpHint text={option.hint} />
+                </div>
+              </div>
+              {selected && (
+                <span className="flex h-5 w-5 shrink-0 items-center justify-center rounded-full bg-primary text-primary-foreground">
+                  <Check size={12} />
+                </span>
+              )}
+            </div>
+          </div>
+        );
+      })}
+    </div>
+  );
+}
+
 function TextAreaField({
   label,
   value,