diff --git a/web/hwlab-cloud-web/scripts/workbench-server-state.test.ts b/web/hwlab-cloud-web/scripts/workbench-server-state.test.ts
index 9001a575..79d80870 100644
--- a/web/hwlab-cloud-web/scripts/workbench-server-state.test.ts
+++ b/web/hwlab-cloud-web/scripts/workbench-server-state.test.ts
@@ -156,3 +156,28 @@ test("Workbench session messages keep sealed terminal timing on bulk refresh", (
   assert.equal(agent?.timing?.durationMs, 12_000);
   assert.equal(agent?.finishedAt, "2026-06-24T00:00:12.000Z");
 });
+
+test("Workbench server-state keeps running card startedAt stable across early snapshots", () => {
+  let state = createWorkbenchServerState();
+  state = reduceWorkbenchServerState(state, {
+    type: "session.messages",
+    sessionId: "ses_running_seal",
+    messages: [
+      { id: "msg_user", messageId: "msg_user", role: "user", title: "用户", text: "ping", status: "sent", createdAt: "2026-06-24T00:00:00.000Z", sessionId: "ses_running_seal", traceId: "trc_running_seal" },
+      { id: "msg_agent", messageId: "msg_agent", role: "agent", title: "Code Agent", text: "", status: "running", createdAt: "2026-06-24T00:00:01.000Z", sessionId: "ses_running_seal", traceId: "trc_running_seal", traceAutoLifecycle: "running", timing: { startedAt: "2026-06-24T00:00:01.000Z", lastEventAt: "2026-06-24T00:00:01.000Z", durationMs: null, valuesRedacted: true }, startedAt: "2026-06-24T00:00:01.000Z", lastEventAt: "2026-06-24T00:00:01.000Z", durationMs: null }
+    ]
+  });
+
+  state = reduceWorkbenchServerState(state, {
+    type: "message.snapshot",
+    sessionId: "ses_running_seal",
+    message: { id: "msg_agent", messageId: "msg_agent", role: "agent", title: "Code Agent", text: "", status: "running", createdAt: "2026-06-24T00:00:02.000Z", sessionId: "ses_running_seal", traceId: "trc_running_seal", timing: { startedAt: "2026-06-24T00:00:02.000Z", lastEventAt: "2026-06-24T00:00:02.000Z", durationMs: 0, valuesRedacted: true }, startedAt: "2026-06-24T00:00:02.000Z", lastEventAt: "2026-06-24T00:00:02.000Z", durationMs: 0 }
+  });
+
+  const agent = selectActiveMessages(state, "ses_running_seal").find((message) => message.role === "agent");
+  assert.equal(agent?.startedAt, "2026-06-24T00:00:01.000Z");
+  assert.equal(agent?.timing?.startedAt, "2026-06-24T00:00:01.000Z");
+  assert.equal(agent?.durationMs, null);
+  assert.equal(agent?.timing?.durationMs, null);
+  assert.equal(agent?.lastEventAt, "2026-06-24T00:00:02.000Z");
+});
diff --git a/web/hwlab-cloud-web/src/stores/workbench-server-state.ts b/web/hwlab-cloud-web/src/stores/workbench-server-state.ts
index f05157bd..5e77a4ad 100644
--- a/web/hwlab-cloud-web/src/stores/workbench-server-state.ts
+++ b/web/hwlab-cloud-web/src/stores/workbench-server-state.ts
@@ -173,16 +173,37 @@ function mergeMessageSnapshot(existing: ChatMessage, incoming: ChatMessage): Cha
     traceAutoLifecycle: existing.traceAutoLifecycle,
     updatedAt: incoming.updatedAt ?? existing.updatedAt
   };
-  return sealExistingTerminalMessageTiming(existing, merged);
+  return sealExistingMessageTiming(existing, merged);
 }
 
 function mergeMessageList(existing: ChatMessage[], incoming: ChatMessage[]): ChatMessage[] {
   return incoming.map((message) => {
     const previous = existing.find((item) => messageMatchesSnapshot(item, message));
-    return previous ? sealExistingTerminalMessageTiming(previous, message) : message;
+    return previous ? sealExistingMessageTiming(previous, message) : message;
   });
 }
 
+function sealExistingMessageTiming(existing: ChatMessage, incoming: ChatMessage): ChatMessage {
+  if (isTerminalMessageStatus(existing.status)) return sealExistingTerminalMessageTiming(existing, incoming);
+  return sealExistingRunningMessageTiming(existing, incoming);
+}
+
+function sealExistingRunningMessageTiming(existing: ChatMessage, incoming: ChatMessage): ChatMessage {
+  if (!isRunningAgentMessageForTiming(existing) || !isRunningAgentMessageForTiming(incoming)) return incoming;
+  const existingTiming = messageTimingProjection(existing);
+  if (!existingTiming?.startedAt) return incoming;
+  const incomingTiming = messageTimingProjection(incoming) ?? null;
+  const timing: NonNullable<ChatMessage["timing"]> = {
+    ...(incomingTiming ?? {}),
+    startedAt: existingTiming.startedAt,
+    lastEventAt: incomingTiming?.lastEventAt ?? existingTiming.lastEventAt ?? existingTiming.startedAt,
+    finishedAt: null,
+    durationMs: null,
+    valuesRedacted: incomingTiming?.valuesRedacted !== false && existingTiming.valuesRedacted !== false,
+  };
+  return { ...incoming, timing, startedAt: timing.startedAt ?? null, lastEventAt: timing.lastEventAt ?? null, finishedAt: null, durationMs: null };
+}
+
 function sealExistingTerminalMessageTiming(existing: ChatMessage, incoming: ChatMessage): ChatMessage {
   if (!isTerminalMessageStatus(existing.status)) return incoming;
   const timing = terminalTimingProjection(existing);
@@ -201,6 +222,10 @@ function sealExistingTerminalMessageTiming(existing: ChatMessage, incoming: Chat
 }
 
 function terminalTimingProjection(message: ChatMessage): ChatMessage["timing"] | null {
+  return messageTimingProjection(message);
+}
+
+function messageTimingProjection(message: ChatMessage): ChatMessage["timing"] | null {
   const timing = message.timing && typeof message.timing === "object" ? message.timing : null;
   const startedAt = timestampOrNull(timing?.startedAt ?? message.startedAt);
   const lastEventAt = timestampOrNull(timing?.lastEventAt ?? message.lastEventAt);
@@ -210,8 +235,19 @@ function terminalTimingProjection(message: ChatMessage): ChatMessage["timing"] |
   return { ...(timing ?? {}), startedAt, lastEventAt, finishedAt, durationMs, valuesRedacted: timing?.valuesRedacted !== false };
 }
 
+function isRunningAgentMessageForTiming(message: ChatMessage): boolean {
+  if (message.role !== "agent") return false;
+  const status = normalizedMessageStatus(message.status);
+  if (isTerminalMessageStatus(status)) return false;
+  return status === "" || status === "pending" || status === "running" || message.traceAutoLifecycle === "running";
+}
+
 function isTerminalMessageStatus(value: unknown): boolean {
-  return ["completed", "failed", "blocked", "timeout", "canceled", "cancelled", "stale", "thread-resume-failed"].includes(String(value ?? "").trim().toLowerCase().replace(/_/gu, "-"));
+  return ["completed", "failed", "blocked", "timeout", "canceled", "cancelled", "stale", "thread-resume-failed"].includes(normalizedMessageStatus(value));
+}
+
+function normalizedMessageStatus(value: unknown): string {
+  return String(value ?? "").trim().toLowerCase().replace(/_/gu, "-");
 }
 
 function timestampOrNull(value: unknown): string | null {