diff --git a/web/hwlab-cloud-web/src/components/agent/TraceTimeline.vue b/web/hwlab-cloud-web/src/components/agent/TraceTimeline.vue
index d01b03c7..97aa27f0 100644
--- a/web/hwlab-cloud-web/src/components/agent/TraceTimeline.vue
+++ b/web/hwlab-cloud-web/src/components/agent/TraceTimeline.vue
@@ -116,7 +116,7 @@ function traceRecord(trace: RunnerTrace | null | undefined): Record<string, unkn
             </template>
           </li>
         </ol>
-        <p v-if="readableRows.length === 0" class="trace-empty">等待后端事件。</p>
+        <p v-if="readableRows.length === 0" class="trace-empty">思考中...</p>
       </div>
     </details>
   </section>
diff --git a/web/hwlab-cloud-web/src/components/workbench/SessionRail.vue b/web/hwlab-cloud-web/src/components/workbench/SessionRail.vue
index 1d81f01d..1c67fa8d 100644
--- a/web/hwlab-cloud-web/src/components/workbench/SessionRail.vue
+++ b/web/hwlab-cloud-web/src/components/workbench/SessionRail.vue
@@ -2,7 +2,6 @@
 import { computed, ref } from "vue";
 import { useWorkbenchStore } from "@/stores/workbench";
 import { useClipboard } from "@/composables/useClipboard";
-import { formatRelativeTime } from "@/utils";
 
 const workbench = useWorkbenchStore();
 const { copied, copy } = useClipboard();
@@ -51,6 +50,18 @@ function readWidth(): number {
     return 300;
   }
 }
+
+function formatSessionUpdatedTime(value: string | null | undefined): string {
+  if (!value) return "未记录";
+  const date = new Date(value);
+  if (!Number.isFinite(date.getTime())) return value;
+  const delta = Date.now() - date.getTime();
+  if (delta < 60_000) return "刚刚";
+  if (delta < 3_600_000) return `${Math.max(1, Math.round(delta / 60_000))} 分`;
+  if (delta < 86_400_000) return `${Math.max(1, Math.round(delta / 3_600_000))} 时`;
+  if (delta < 604_800_000) return `${Math.max(1, Math.round(delta / 86_400_000))} 天`;
+  return date.toLocaleString(undefined, { month: "numeric", day: "numeric", hour: "2-digit", minute: "2-digit" });
+}
 </script>
 
 <template>
@@ -64,11 +75,9 @@ function readWidth(): number {
     </div>
     <div class="session-model-channel" id="session-model-channel">模型通道：{{ workbench.providerProfile }}</div>
     <div class="session-list" id="session-tabs">
-      <button v-for="tab in workbench.sessionTabs" :key="tab.conversationId" class="session-tab" :data-active="tab.active" type="button" @click="workbench.selectConversation(tab)">
-        <strong>{{ tab.label || tab.conversationId }}</strong>
-        <span>{{ tab.sessionId || "未绑定 session" }}</span>
-        <span>{{ tab.subtitle }}</span>
-        <small>{{ formatRelativeTime(tab.updatedAt || tab.startedAt) }}</small>
+      <button v-for="tab in workbench.sessionTabs" :key="tab.conversationId" class="session-tab" :data-active="tab.active" type="button" :title="tab.label || tab.conversationId" @click="workbench.selectConversation(tab)">
+        <span class="session-tab-title">{{ tab.label || tab.conversationId }}</span>
+        <time class="session-tab-time" :datetime="tab.updatedAt || tab.startedAt || undefined">{{ formatSessionUpdatedTime(tab.updatedAt || tab.startedAt) }}</time>
       </button>
       <p v-if="workbench.sessionTabs.length === 0" class="muted-box">没有 session。发送前必须显式新建或选择 session。</p>
     </div>
diff --git a/web/hwlab-cloud-web/src/stores/workbench-session.ts b/web/hwlab-cloud-web/src/stores/workbench-session.ts
index ff56ed74..37d8d13e 100644
--- a/web/hwlab-cloud-web/src/stores/workbench-session.ts
+++ b/web/hwlab-cloud-web/src/stores/workbench-session.ts
@@ -93,20 +93,20 @@ export function conversationToSessionTab(conversation: ConversationRecord, activ
   const status = firstNonEmptyString(conversation.snapshot?.sessionStatus, conversation.status, conversation.messages?.at(-1)?.status) ?? "source";
   const trace = firstNonEmptyString(conversation.lastTraceId, conversation.messages?.at(-1)?.traceId);
   const userMessage = conversation.messages?.find((message) => message.role === "user");
-  const preview = firstReadableText(
+  const preview = firstReadableSentence(
     conversation.firstUserMessagePreview,
     conversation.snapshot?.firstUserMessagePreview,
     conversation.userPreview,
-    conversation.title,
-    conversation.name,
     userMessage?.text,
     userMessage?.content,
-    userMessage?.title
+    userMessage?.title,
+    conversation.title,
+    conversation.name
   );
   return {
     ...conversation,
     key: sessionId ?? conversationId,
-    label: truncateLabel(preview) ?? `Session ${shortToken(sessionId ?? conversationId, 8)}`,
+    label: preview ?? `Session ${shortToken(sessionId ?? conversationId, 8)}`,
     subtitle: `${status === "running" ? "处理中" : trace ? `trace ${shortToken(trace, 8)}` : "未开始"} · ${conversation.messageCount ?? conversation.messages?.length ?? 0} 条`,
     sessionId,
     threadId: firstNonEmptyString(conversation.threadId, conversation.session?.threadId),
@@ -215,31 +215,21 @@ function compareProviderProfileOptions(left: ProviderProfileOption, right: Provi
   return left.value.localeCompare(right.value);
 }
 
-function truncateLabel(value: string | null): string | null {
-  if (!value) return null;
-  const text = value.replace(/\s+/gu, " ").trim();
-  if (!text || text === OBJECT_OBJECT_TEXT) return null;
-  return text.length <= 36 ? text : `${text.slice(0, 36).trimEnd()}...`;
-}
-
-function firstReadableText(...values: unknown[]): string | null {
+function firstReadableSentence(...values: unknown[]): string | null {
   for (const value of values) {
-    const text = readableText(value);
+    const text = readableSentence(value);
     if (text) return text;
   }
   return null;
 }
 
-function readableText(value: unknown): string | null {
-  if (typeof value === "string") {
-    const text = value.replace(/\s+/gu, " ").trim();
-    return text && text !== OBJECT_OBJECT_TEXT ? text : null;
-  }
+function readableSentence(value: unknown): string | null {
+  if (typeof value === "string") return firstSentenceFromText(value);
   if (typeof value === "number" || typeof value === "boolean") return String(value);
-  if (Array.isArray(value)) return firstReadableText(...value);
+  if (Array.isArray(value)) return firstReadableSentence(...value);
   if (!value || typeof value !== "object") return null;
   const record = value as Record<string, unknown>;
-  return firstReadableText(
+  return firstReadableSentence(
     record.text,
     record.content,
     record.message,
@@ -252,6 +242,24 @@ function readableText(value: unknown): string | null {
   );
 }
 
+function firstSentenceFromText(value: string): string | null {
+  const normalized = value.replace(/\u0000/gu, " ").replace(/\r\n|\r/gu, "\n").replace(/[\t\f\v ]+/gu, " ").trim();
+  if (!normalized || normalized === OBJECT_OBJECT_TEXT) return null;
+  const candidates = [
+    sentenceBoundary(normalized, /[。！？!?]/u, 1),
+    sentenceBoundary(normalized, /\.(?=\s|$)/u, 1),
+    sentenceBoundary(normalized, /\n+/u, 0)
+  ].filter((index): index is number => typeof index === "number");
+  const end = candidates.length > 0 ? Math.min(...candidates) : normalized.length;
+  const text = normalized.slice(0, end).replace(/\s+/gu, " ").trim();
+  return text && text !== OBJECT_OBJECT_TEXT ? text : null;
+}
+
+function sentenceBoundary(value: string, pattern: RegExp, offset: number): number | null {
+  const match = pattern.exec(value);
+  return match?.index === undefined ? null : match.index + offset;
+}
+
 function shortToken(value: string | null | undefined, size: number): string {
   const text = String(value ?? "");
   if (text.length <= size) return text;
diff --git a/web/hwlab-cloud-web/src/styles/workbench.css b/web/hwlab-cloud-web/src/styles/workbench.css
index 80fa5589..4e65ce7d 100644
--- a/web/hwlab-cloud-web/src/styles/workbench.css
+++ b/web/hwlab-cloud-web/src/styles/workbench.css
@@ -606,13 +606,16 @@
 }
 
 .session-tab {
-  display: grid;
+  display: flex;
+  align-items: center;
+  min-width: 0;
+  min-height: 34px;
   width: 100%;
-  gap: 4px;
+  gap: 10px;
   border: 1px solid #e2e8f0;
-  border-radius: 8px;
+  border-radius: 6px;
   background: #f8fafc;
-  padding: 10px;
+  padding: 7px 9px;
   color: #334155;
   text-align: left;
 }
@@ -622,16 +625,27 @@
   background: #f0f9ff;
 }
 
-.session-tab strong,
-.session-tab span,
-.session-tab small {
+.session-tab-title {
+  min-width: 0;
+  flex: 1 1 auto;
+  color: #0f172a;
+  font-size: 13px;
+  font-weight: 600;
   overflow: hidden;
   text-overflow: ellipsis;
   white-space: nowrap;
 }
 
-.session-tab span,
-.session-tab small,
+.session-tab-time {
+  flex: 0 0 auto;
+  color: #64748b;
+  font-size: 12px;
+  font-variant-numeric: tabular-nums;
+  line-height: 1;
+  text-align: right;
+  white-space: nowrap;
+}
+
 .muted-box {
   color: #64748b;
   font-size: 12px;