diff --git a/web/hwlab-cloud-web/src/components/workbench/ConversationPanel.vue b/web/hwlab-cloud-web/src/components/workbench/ConversationPanel.vue
index 1821ad3f..993ca790 100644
--- a/web/hwlab-cloud-web/src/components/workbench/ConversationPanel.vue
+++ b/web/hwlab-cloud-web/src/components/workbench/ConversationPanel.vue
@@ -233,7 +233,8 @@ function traceForDisplay(message: ChatMessage): ChatMessage["runnerTrace"] {
 
 function messageDurationMeta(message: ChatMessage): { text: string; label: string } | null {
   if (message.role !== "agent") return null;
-  const durationMs = isRunningMessage(message) ? durationSince(message.timing?.startedAt) : finiteDurationMs(message.timing?.durationMs);
+  const timing = messageTimingForDisplay(message);
+  const durationMs = isRunningMessage(message) ? durationSince(timing?.startedAt) : finiteDurationMs(timing?.durationMs);
   if (durationMs === null) return null;
   const value = formatDuration(durationMs);
   return { text: `耗时 ${value}`, label: `总耗时：${value}` };
@@ -241,12 +242,17 @@ function messageDurationMeta(message: ChatMessage): { text: string; label: strin
 
 function messageActivityMeta(message: ChatMessage): { text: string; label: string } | null {
   if (!isRunningMessage(message)) return null;
-  const ageMs = durationSince(message.timing?.lastEventAt);
+  const timing = messageTimingForDisplay(message);
+  const ageMs = durationSince(timing?.lastEventAt);
   if (ageMs === null) return null;
   const value = formatDuration(ageMs) + "前";
   return { text: `最近 ${value}`, label: `最近事件：${value}` };
 }
 
+function messageTimingForDisplay(message: ChatMessage): ChatMessage["timing"] {
+  return message.runnerTrace?.timing ?? message.timing ?? null;
+}
+
 function durationSince(timestamp: unknown): number | null {
   const startedAtMs = timestampMs(timestamp);
   return startedAtMs === null ? null : Math.max(0, nowMs.value - startedAtMs);
diff --git a/web/hwlab-cloud-web/src/composables/useTraceSubscription.ts b/web/hwlab-cloud-web/src/composables/useTraceSubscription.ts
index c52b0ee7..1d316771 100644
--- a/web/hwlab-cloud-web/src/composables/useTraceSubscription.ts
+++ b/web/hwlab-cloud-web/src/composables/useTraceSubscription.ts
@@ -118,7 +118,128 @@ export function mergeRunnerTrace(previous: ChatMessage["runnerTrace"], next: Non
     : keepPreviousEvents && previousAuthoritative && next.eventsCompacted === true ? previousEvents
       : keepPreviousEvents ? mergeTraceEvents(previousEvents, nextEvents) : nextEvents.length > previousEvents.length ? mergeTraceEvents(previousEvents, nextEvents) : nextEvents;
   const eventCount = keepPreviousEvents ? previous.eventCount ?? events.length : next.eventCount ?? previous.eventCount ?? events.length;
-  return { ...previous, ...next, events, eventCount, updatedAt: next.updatedAt ?? previous.updatedAt ?? new Date().toISOString() };
+  const timing = mergeTraceTimingProjection(previous, next, { preserveVisibleTerminalDuration: traceTimingWasRunning(previous) && traceTimingIsTerminal(next) });
+  return {
+    ...previous,
+    ...next,
+    events,
+    eventCount,
+    timing,
+    startedAt: timing?.startedAt ?? next.startedAt ?? previous.startedAt ?? null,
+    lastEventAt: timing?.lastEventAt ?? next.lastEventAt ?? previous.lastEventAt ?? null,
+    finishedAt: timing?.finishedAt ?? next.finishedAt ?? previous.finishedAt ?? null,
+    durationMs: timing?.durationMs ?? next.durationMs ?? previous.durationMs ?? null,
+    updatedAt: next.updatedAt ?? previous.updatedAt ?? new Date().toISOString()
+  };
+}
+
+function mergeTraceTimingProjection(previous: unknown, next: unknown, options: { preserveVisibleTerminalDuration?: boolean } = {}): TraceSnapshot["timing"] | null {
+  const previousTiming = traceTimingCandidate(previous);
+  const nextTiming = traceTimingCandidate(next);
+  if (!previousTiming && !nextTiming) return null;
+  if (!previousTiming) return nextTiming;
+  if (!nextTiming) return previousTiming;
+  const startedAt = earliestTraceTimestamp(previousTiming.startedAt, nextTiming.startedAt);
+  const lastEventAt = latestTraceTimestamp(previousTiming.lastEventAt, nextTiming.lastEventAt);
+  const finishedAt = latestTraceTimestamp(previousTiming.finishedAt, nextTiming.finishedAt);
+  const elapsedDurationMs = traceElapsedMs(startedAt, finishedAt ?? lastEventAt);
+  const visibleTerminalDurationMs = options.preserveVisibleTerminalDuration === true ? traceElapsedMs(startedAt, new Date().toISOString()) : null;
+  const durationMs = maxTraceDuration(previousTiming.durationMs, nextTiming.durationMs, elapsedDurationMs, visibleTerminalDurationMs);
+  return {
+    ...previousTiming,
+    ...nextTiming,
+    startedAt,
+    lastEventAt,
+    finishedAt,
+    durationMs,
+    observedAt: latestTraceTimestamp(previousTiming.observedAt, nextTiming.observedAt),
+    lastEventAgeMs: null,
+    valuesRedacted: previousTiming.valuesRedacted !== false && nextTiming.valuesRedacted !== false
+  };
+}
+
+function traceTimingCandidate(value: unknown): TraceSnapshot["timing"] | null {
+  const record = traceRecord(value);
+  const timing = traceRecord(record?.timing);
+  if (!record && !timing) return null;
+  const startedAt = firstTraceTimestamp(timing?.startedAt, record?.startedAt);
+  const lastEventAt = firstTraceTimestamp(timing?.lastEventAt, record?.lastEventAt);
+  const finishedAt = firstTraceTimestamp(timing?.finishedAt, record?.finishedAt);
+  const observedAt = firstTraceTimestamp(timing?.observedAt, record?.observedAt);
+  const durationMs = maxTraceDuration(timing?.durationMs, record?.durationMs);
+  const lastEventAgeMs = finiteTraceDuration(timing?.lastEventAgeMs ?? record?.lastEventAgeMs);
+  if (!startedAt && !lastEventAt && !finishedAt && !observedAt && durationMs === null && lastEventAgeMs === null) return null;
+  return { ...(timing ?? {}), startedAt, lastEventAt, finishedAt, observedAt, durationMs, lastEventAgeMs, valuesRedacted: timing?.valuesRedacted !== false };
+}
+
+function traceRecord(value: unknown): Record<string, unknown> | null {
+  return value && typeof value === "object" ? value as Record<string, unknown> : null;
+}
+
+function firstTraceTimestamp(...values: unknown[]): string | null {
+  for (const value of values) {
+    if (typeof value !== "string") continue;
+    const text = value.trim();
+    if (!text) continue;
+    if (Number.isFinite(Date.parse(text))) return text;
+  }
+  return null;
+}
+
+function earliestTraceTimestamp(...values: unknown[]): string | null {
+  return selectTraceTimestamp("earliest", values);
+}
+
+function latestTraceTimestamp(...values: unknown[]): string | null {
+  return selectTraceTimestamp("latest", values);
+}
+
+function selectTraceTimestamp(mode: "earliest" | "latest", values: unknown[]): string | null {
+  let selected: { value: string; ms: number } | null = null;
+  for (const value of values) {
+    const timestamp = firstTraceTimestamp(value);
+    if (!timestamp) continue;
+    const ms = Date.parse(timestamp);
+    if (!selected || (mode === "earliest" ? ms < selected.ms : ms > selected.ms)) selected = { value: timestamp, ms };
+  }
+  return selected?.value ?? null;
+}
+
+function traceElapsedMs(startedAt: unknown, endedAt: unknown): number | null {
+  const start = startedAt == null ? NaN : Date.parse(String(startedAt));
+  const end = endedAt == null ? NaN : Date.parse(String(endedAt));
+  if (!Number.isFinite(start) || !Number.isFinite(end) || end < start) return null;
+  return Math.trunc(end - start);
+}
+
+function maxTraceDuration(...values: unknown[]): number | null {
+  let max: number | null = null;
+  for (const value of values) {
+    const duration = finiteTraceDuration(value);
+    if (duration === null) continue;
+    if (max === null || duration > max) max = duration;
+  }
+  return max;
+}
+
+function finiteTraceDuration(value: unknown): number | null {
+  const number = Number(value);
+  return Number.isFinite(number) && number >= 0 ? Math.trunc(number) : null;
+}
+
+function traceTimingWasRunning(value: unknown): boolean {
+  const record = traceRecord(value);
+  if (!record) return false;
+  const status = typeof record.status === "string" ? record.status.trim().toLowerCase() : "";
+  if (["completed", "failed", "cancelled", "canceled", "error"].includes(status)) return false;
+  const timing = traceTimingCandidate(value);
+  return !timing?.finishedAt;
+}
+
+function traceTimingIsTerminal(value: unknown): boolean {
+  const record = traceRecord(value);
+  const status = typeof record?.status === "string" ? record.status.trim().toLowerCase() : "";
+  return ["completed", "failed", "cancelled", "canceled", "error"].includes(status) || traceTimingCandidate(value)?.finishedAt != null;
 }
 
 function mergeTraceEvents(previousEvents: TraceEvent[], nextEvents: TraceEvent[]): TraceEvent[] {
@@ -298,22 +419,24 @@ function mergeTraceSnapshots(previous: TraceSnapshot | null, next: TraceSnapshot
   const previousEvents = Array.isArray(previous.events) ? previous.events : [];
   const nextEvents = Array.isArray(next.events) ? next.events : [];
   const events = mergeTraceEvents(previousEvents, nextEvents);
+  const timing = mergeTraceTimingProjection(previous, next, { preserveVisibleTerminalDuration: traceTimingWasRunning(previous) && traceTimingIsTerminal(next) });
   return {
     ...previous,
     ...next,
     events,
     eventCount: next.eventCount ?? previous.eventCount ?? events.length,
-    timing: next.timing ?? previous.timing ?? null,
-    startedAt: next.startedAt ?? next.timing?.startedAt ?? previous.startedAt ?? previous.timing?.startedAt ?? null,
-    lastEventAt: next.lastEventAt ?? next.timing?.lastEventAt ?? previous.lastEventAt ?? previous.timing?.lastEventAt ?? null,
-    finishedAt: next.finishedAt ?? next.timing?.finishedAt ?? previous.finishedAt ?? previous.timing?.finishedAt ?? null,
-    durationMs: next.durationMs ?? next.timing?.durationMs ?? previous.durationMs ?? previous.timing?.durationMs ?? null,
+    timing,
+    startedAt: timing?.startedAt ?? next.startedAt ?? next.timing?.startedAt ?? previous.startedAt ?? previous.timing?.startedAt ?? null,
+    lastEventAt: timing?.lastEventAt ?? next.lastEventAt ?? next.timing?.lastEventAt ?? previous.lastEventAt ?? previous.timing?.lastEventAt ?? null,
+    finishedAt: timing?.finishedAt ?? next.finishedAt ?? next.timing?.finishedAt ?? previous.finishedAt ?? previous.timing?.finishedAt ?? null,
+    durationMs: timing?.durationMs ?? next.durationMs ?? next.timing?.durationMs ?? previous.durationMs ?? previous.timing?.durationMs ?? null,
     lastEventLabel: next.lastEventLabel ?? previous.lastEventLabel ?? undefined,
     updatedAt: next.updatedAt ?? previous.updatedAt ?? new Date().toISOString()
   };
 }
 
 function traceSnapshotWithTurnStatus(trace: TraceSnapshot, turn: TraceSnapshot): TraceSnapshot {
+  const timing = mergeTraceTimingProjection(trace, turn, { preserveVisibleTerminalDuration: traceTimingWasRunning(trace) && traceTimingIsTerminal(turn) });
   return {
     ...trace,
     traceId: trace.traceId ?? turn.traceId,
@@ -325,11 +448,11 @@ function traceSnapshotWithTurnStatus(trace: TraceSnapshot, turn: TraceSnapshot):
     terminalEvidence: trace.terminalEvidence ?? turn.terminalEvidence,
     traceSummary: trace.traceSummary ?? turn.traceSummary,
     error: trace.error ?? turn.error,
-    timing: turn.timing ?? trace.timing ?? null,
-    startedAt: turn.startedAt ?? turn.timing?.startedAt ?? trace.startedAt ?? trace.timing?.startedAt ?? null,
-    lastEventAt: turn.lastEventAt ?? turn.timing?.lastEventAt ?? trace.lastEventAt ?? trace.timing?.lastEventAt ?? null,
-    finishedAt: turn.finishedAt ?? turn.timing?.finishedAt ?? trace.finishedAt ?? trace.timing?.finishedAt ?? null,
-    durationMs: turn.durationMs ?? turn.timing?.durationMs ?? trace.durationMs ?? trace.timing?.durationMs ?? null,
+    timing,
+    startedAt: timing?.startedAt ?? turn.startedAt ?? turn.timing?.startedAt ?? trace.startedAt ?? trace.timing?.startedAt ?? null,
+    lastEventAt: timing?.lastEventAt ?? turn.lastEventAt ?? turn.timing?.lastEventAt ?? trace.lastEventAt ?? trace.timing?.lastEventAt ?? null,
+    finishedAt: timing?.finishedAt ?? turn.finishedAt ?? turn.timing?.finishedAt ?? trace.finishedAt ?? trace.timing?.finishedAt ?? null,
+    durationMs: timing?.durationMs ?? turn.durationMs ?? turn.timing?.durationMs ?? trace.durationMs ?? trace.timing?.durationMs ?? null,
     projection: trace.projection ?? turn.projection ?? null,
     projectionStatus: trace.projectionStatus ?? turn.projectionStatus ?? null,
     projectionHealth: trace.projectionHealth ?? turn.projectionHealth ?? null,