diff --git a/web/hwlab-cloud-web/scripts/workbench-performance.test.ts b/web/hwlab-cloud-web/scripts/workbench-performance.test.ts
new file mode 100644
index 00000000..9a51b4e7
--- /dev/null
+++ b/web/hwlab-cloud-web/scripts/workbench-performance.test.ts
@@ -0,0 +1,65 @@
+// SPEC: PJ2026-01060505 Workbench Performance draft-2026-06-17-p0
+// Exercises the browser-side Workbench performance probe without sending network traffic.
+
+import assert from "node:assert/strict";
+import test from "node:test";
+
+import type { ChatMessage, TraceEvent } from "../src/types/index.ts";
+import {
+  acknowledgeWorkbenchVisible,
+  drainWorkbenchPerformanceEventsForTest,
+  finishWorkbenchOpenFullLoad,
+  finishWorkbenchSessionSwitchFullLoad,
+  markWorkbenchSubmitApiAccepted,
+  markWorkbenchTraceEventsReceived,
+  markWorkbenchTraceProjected,
+  resetWorkbenchPerformanceForTest,
+  startWorkbenchOpenJourney,
+  startWorkbenchSessionSwitch,
+  startWorkbenchSubmitJourney
+} from "../src/utils/workbench-performance.ts";
+
+test("Workbench performance probe records journeys and strips high-cardinality identifiers", () => {
+  resetWorkbenchPerformanceForTest();
+  startWorkbenchOpenJourney({ route: "/workbench/sessions/cnv_secret", cache: "cold", authState: "warm" });
+  acknowledgeWorkbenchVisible({ messages: [], activeConversationId: "cnv_secret", detailLoading: false });
+  finishWorkbenchOpenFullLoad("ok");
+
+  startWorkbenchSessionSwitch({ conversationId: "cnv_secret", source: "rail", targetState: "running", cache: "warm" });
+  acknowledgeWorkbenchVisible({ messages: [userMessage("cnv_secret")], activeConversationId: "cnv_secret", detailLoading: false });
+  finishWorkbenchSessionSwitchFullLoad("cnv_secret", "ok");
+
+  const createdAt = new Date(Date.now() - 250).toISOString();
+  startWorkbenchSubmitJourney({ traceId: "trc_secret", conversationId: "cnv_secret", entry: "existing", backend: "codex", transport: "sse" });
+  markWorkbenchSubmitApiAccepted("trc_secret");
+  markWorkbenchTraceEventsReceived({ traceId: "trc_secret", transport: "sse", events: [{ type: "assistant_message", createdAt, ts: createdAt } as TraceEvent] });
+  markWorkbenchTraceProjected("trc_secret");
+  acknowledgeWorkbenchVisible({ messages: [agentMessage("cnv_secret", "trc_secret")], activeConversationId: "cnv_secret", detailLoading: false });
+
+  const events = drainWorkbenchPerformanceEventsForTest();
+  const payload = JSON.stringify(events);
+  assert.ok(events.some((event) => event.kind === "workbench_journey" && event.journey === "workbench_open_first_visible"));
+  assert.ok(events.some((event) => event.kind === "workbench_journey" && event.journey === "session_switch_first_visible"));
+  assert.ok(events.some((event) => event.kind === "workbench_journey" && event.journey === "submit_to_first_visible" && event.backend === "agentrun-v01/codex"));
+  assert.ok(events.some((event) => event.kind === "workbench_event_phase" && event.phase === "project_to_paint"));
+  assert.ok(events.some((event) => event.kind === "workbench_backend_event_visible" && event.eventType === "assistant"));
+  assert.doesNotMatch(payload, /trc_secret|cnv_secret|sessionId|conversationId|runId|commandId/u);
+});
+
+function userMessage(conversationId: string): ChatMessage {
+  return { id: "msg_user", role: "user", title: "User", text: "hello", status: "sent", createdAt: new Date().toISOString(), conversationId };
+}
+
+function agentMessage(conversationId: string, traceId: string): ChatMessage {
+  return {
+    id: "msg_agent",
+    role: "agent",
+    title: "Code Agent",
+    text: "visible",
+    status: "running",
+    createdAt: new Date().toISOString(),
+    conversationId,
+    traceId,
+    runnerTrace: { traceId, eventCount: 1, events: [{ type: "assistant_message" }] }
+  };
+}
diff --git a/web/hwlab-cloud-web/src/components/workbench/ConversationPanel.vue b/web/hwlab-cloud-web/src/components/workbench/ConversationPanel.vue
index f4a351ef..a0df1189 100644
--- a/web/hwlab-cloud-web/src/components/workbench/ConversationPanel.vue
+++ b/web/hwlab-cloud-web/src/components/workbench/ConversationPanel.vue
@@ -1,4 +1,7 @@
 <script setup lang="ts">
+// SPEC: PJ2026-01060505 Workbench Performance draft-2026-06-17-p0
+// Confirms Workbench message visibility after Vue render and browser paint.
+
 import { computed, nextTick, onMounted, ref, watch } from "vue";
 import type { ChatMessage } from "@/types";
 import LoadingState from "@/components/common/LoadingState.vue";
@@ -10,6 +13,7 @@ import MessageMarkdown from "@/components/workbench/MessageMarkdown.vue";
 import MessageTraceDebugPanel from "@/components/workbench/MessageTraceDebugPanel.vue";
 import { useClipboard } from "@/composables/useClipboard";
 import { useWorkbenchStore } from "@/stores/workbench";
+import { acknowledgeWorkbenchVisibleAfterPaint } from "@/utils/workbench-performance";
 import { traceIdentityText } from "./message-rendering";
 import { traceLifecycleExpanded } from "./trace-lifecycle";
 
@@ -32,11 +36,18 @@ watch(scrollSignature, async () => {
   if (!following.value) return;
   await nextTick();
   scrollToBottom();
+  acknowledgeVisibleMessages();
 });
 
 onMounted(async () => {
   await nextTick();
   scrollToBottom();
+  acknowledgeVisibleMessages();
+});
+
+watch(() => workbench.conversationDetailLoading, async () => {
+  await nextTick();
+  acknowledgeVisibleMessages();
 });
 
 function openDetails(message: ChatMessage): void {
@@ -71,6 +82,10 @@ function scrollToBottom(): void {
   panel.scrollTop = panel.scrollHeight;
 }
 
+function acknowledgeVisibleMessages(): void {
+  acknowledgeWorkbenchVisibleAfterPaint({ messages: workbench.messages, activeConversationId: workbench.activeConversationId, detailLoading: workbench.conversationDetailLoading });
+}
+
 function traceStorageKey(message: ChatMessage): string {
   return `hwlab.workbench.trace-open.${message.traceId ?? message.runnerTrace?.traceId ?? message.id}`;
 }
diff --git a/web/hwlab-cloud-web/src/stores/workbench.ts b/web/hwlab-cloud-web/src/stores/workbench.ts
index 928f9e94..2e01c843 100644
--- a/web/hwlab-cloud-web/src/stores/workbench.ts
+++ b/web/hwlab-cloud-web/src/stores/workbench.ts
@@ -1,4 +1,4 @@
-// SPEC: PJ2026-010403 API契约 draft-2026-06-17-r0; PJ2026-010401 Web工作台 draft-2026-06-17-r0.
+// SPEC: PJ2026-010403 API契约 draft-2026-06-17-r0; PJ2026-010401 Web工作台 draft-2026-06-17-r0; PJ2026-01060505 Workbench Performance draft-2026-06-17-p0.
 // Responsibility: Workbench client state orchestration for session selection, turn admission, and trace lifecycle rendering.
 
 import { computed, ref } from "vue";
@@ -8,6 +8,7 @@ import { connectWorkbenchEvents, type WorkbenchEventStream, type WorkbenchRealti
 import { mergeRunnerTrace, snapshotToRunnerTrace, type TraceSnapshot } from "@/composables/useTraceSubscription";
 import type { AgentChatResponse, AgentChatResultResponse, AgentRunProvenance, ApiResult, ChatMessage, ConversationRecord, LiveSurface, ProviderProfile, TraceEvent, WorkspaceRecord } from "@/types";
 import { DEFAULT_WORKBENCH_PROJECT_ID, firstNonEmptyString, nextProtocolId, normalizeWorkbenchConversationId, rememberWorkbenchProjectId, resolveInitialWorkbenchProjectId, workspaceProjectId } from "@/utils";
+import { failWorkbenchSessionSwitch, failWorkbenchSubmitJourney, finishWorkbenchSessionSwitchFullLoad, markWorkbenchSubmitApiAccepted, markWorkbenchTraceEventsReceived, markWorkbenchTraceProjected, startWorkbenchSessionSwitch, startWorkbenchSubmitJourney } from "@/utils/workbench-performance";
 import { RECENT_DRAFTS_STORAGE_KEY, defaultProviderProfileOptions, mergeConversationIntoList, normalizeChatMessageStatus, normalizeRecentDrafts, normalizeWorkbenchMessageTitle, providerProfileOptionsFromPayload, recordRecentDraft, resolveCancelableAgentMessage, resolveComposerState, selectedConversationIdFromWorkspace, shouldApplyWorkspaceSnapshot, shouldShowSessionListLoading, sortSessionTabs, stableConversationList, workspaceWithClearedActiveTrace, type DraftEntry, type ProviderProfileOption, type SessionStatusAuthority, type TurnStatusAuthority } from "./workbench-session";
 import { initialWorkbenchConversationIdFromLocation, nextExplicitWorkbenchConversationId, resolveWorkbenchActiveConversationId } from "./workbench-projection";
 import { createWorkbenchServerState, reduceWorkbenchServerState, selectSessionStatusAuthority, selectTraceAuthorityById, selectTurnStatusAuthority, type WorkbenchServerAction } from "./workbench-server-state";
@@ -184,6 +185,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
     const current = await ensureWorkspace();
     if (!current) return;
     const requestEpoch = beginWorkspaceSelection();
+    startWorkbenchSessionSwitch({ conversationId: conversation.conversationId, source: "rail", targetState: conversation.status, cache: (conversation.messages?.length ?? 0) > 0 ? "warm" : "cold" });
     const tabProjectId = conversation.projectId ?? activeProjectId.value;
     switchingConversationId.value = conversation.conversationId;
     setActiveConversationSelection(conversation.conversationId);
@@ -210,11 +212,13 @@ export const useWorkbenchStore = defineStore("workbench", () => {
       void persistSelectedConversation(selectedConversation, selectedProjectId, response);
       await refreshSelectedSessionStatus(selectedConversation);
       await refreshConversations(conversation.conversationId);
+      finishWorkbenchSessionSwitchFullLoad(conversation.conversationId, "ok");
       return;
     }
     error.value = detailResponse.error ?? "conversation unavailable";
     if (response.status === 404 && await retrySelectConversationWithFreshWorkspace(conversation, tabProjectId, requestEpoch)) return;
     error.value = response.error ?? "session switch failed";
+    failWorkbenchSessionSwitch(conversation.conversationId);
   }
 
   async function selectConversationById(conversationId: string): Promise<boolean> {
@@ -228,6 +232,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
     if (!current) return false;
     if (activeConversationId.value === normalized && messages.value.length > 0) return true;
     const requestEpoch = beginWorkspaceSelection();
+    startWorkbenchSessionSwitch({ conversationId: normalized, source: "deeplink", targetState: "unknown", cache: "cold" });
     switchingConversationId.value = normalized;
     conversationDetailLoadingId.value = normalized;
     const existing = visibleConversations.value.find((conversation) => conversation.conversationId === normalized) ?? null;
@@ -241,6 +246,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
       if (isCurrentWorkspaceSelection(requestEpoch, normalized)) clearSwitchingConversation(normalized);
       clearConversationDetailLoading(normalized);
       error.value = response.error ?? "session URL not found";
+      failWorkbenchSessionSwitch(normalized);
       return false;
     }
     const selectedProjectId = conversationProjectId(conversation, activeProjectId.value);
@@ -251,6 +257,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
     void refreshSessionStatusById(sessionIdFromConversation(conversation));
     void persistSelectedConversation(conversation, selectedProjectId);
     void refreshConversations(normalized);
+    finishWorkbenchSessionSwitchFullLoad(normalized, "ok");
     return activeConversationId.value === normalized && messages.value.length > 0;
   }
 
@@ -464,6 +471,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
       return;
     }
     const steerMode = composer.value.submitMode === "steer";
+    const submitEntry = steerMode ? "steer" : activeConversationId.value ? "existing" : "new";
     const traceId = steerMode && composer.value.targetTraceId ? composer.value.targetTraceId : nextProtocolId("trc");
     const steerTraceId = steerMode ? nextProtocolId("trc_steer") : null;
     const conversationId = activeConversationId.value ?? nextProtocolId("cnv");
@@ -473,6 +481,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
     const user = makeMessage("user", value, "sent", { traceId: steerTraceId ?? traceId, conversationId, sessionId, threadId, title: steerMode ? "用户引导" : "用户" });
     const pending = makeMessage("agent", "", "running", { traceId, conversationId, sessionId, threadId, title: "Code Agent", retryInput: value, traceAutoLifecycle: "running" });
     messages.value.push(user, pending);
+    startWorkbenchSubmitJourney({ traceId, conversationId, entry: submitEntry, backend: providerProfile.value, transport: "sse" });
     void refreshSessionStatusById(sessionId);
     chatPending.value = true;
     currentRequest.value = { traceId, conversationId, sessionId, threadId, status: "running" };
@@ -481,6 +490,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
     const sessionCreate = await waitForPendingSessionCreate(conversationId);
     if (!sessionCreate.ok) {
       markMessage(traceId, { status: "failed", text: `新会话尚未准备好，消息未提交：${sessionCreate.error ?? "session create failed"}` });
+      failWorkbenchSubmitJourney(traceId, "error");
       chatPending.value = false;
       currentRequest.value = null;
       return;
@@ -490,12 +500,14 @@ export const useWorkbenchStore = defineStore("workbench", () => {
     const response = await route(payload, codeAgentTimeoutMs.value, () => activityRef.value);
     if (!response.ok || !response.data) {
       markMessage(traceId, { status: "failed", text: response.error ?? "Code Agent 请求失败" });
+      failWorkbenchSubmitJourney(traceId, response.status === 0 ? "network" : "error");
       if (steerMode && response.status === 404) void clearActiveTrace(traceId, "steer-trace-not-found");
       chatPending.value = false;
       currentRequest.value = null;
       void refreshSessionStatusById(sessionId);
       return;
     }
+    markWorkbenchSubmitApiAccepted(traceId);
     void refreshSessionStatusById(sessionId);
     alignOptimisticTurnMessages(traceId, response.data);
     applyTurnStatusSnapshot(traceId, response.data);
@@ -611,6 +623,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
 
   function applyTraceHydrationResult(traceId: string, result: AgentChatResultResponse): void {
     const events = Array.isArray(result.events) ? result.events : Array.isArray(result.traceEvents) ? result.traceEvents : [];
+    markWorkbenchTraceEventsReceived({ traceId, events, transport: "rest_gap" });
     messages.value = messages.value.map((message) => {
       if (firstNonEmptyString(message.traceId, message.runnerTrace?.traceId) !== traceId || message.role !== "agent") return message;
       const runnerTrace = mergeRunnerTrace(message.runnerTrace, {
@@ -647,6 +660,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
       rememberTraceAuthority(runnerTrace);
       return { ...message, status, text, runnerTrace, error: error ?? message.error ?? null, agentRun: agentRun ?? undefined, updatedAt: new Date().toISOString() };
     });
+    markWorkbenchTraceProjected(traceId);
   }
 
   function setProviderProfile(value: ProviderProfile): void {
@@ -788,6 +802,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
     const id = firstNonEmptyString(traceId, event?.traceId, snapshot?.traceId);
     if (!id) return;
     const events = event ? [event] : Array.isArray(snapshot?.events) ? snapshot.events : [];
+    markWorkbenchTraceEventsReceived({ traceId: id, events, transport: "sse" });
     applyTraceSnapshot(id, realtimeSnapshotToTraceSnapshot(id, snapshot ?? { traceId: id, status: event?.status, events }, events));
     if (event?.terminal === true || isTerminalMessageStatus(event?.status) || isTerminalMessageStatus(snapshot?.status)) void refreshTerminalTraceFromRest(id, "realtime-trace-event");
   }
@@ -867,6 +882,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
       rememberTraceAuthority(runnerTrace);
       return { ...message, status, traceAutoLifecycle: "running", runnerTrace, updatedAt: new Date().toISOString() };
     });
+    markWorkbenchTraceProjected(traceId);
     void refreshSessionStatusById(trace.sessionId ?? selectedSessionId.value);
   }
 
@@ -882,6 +898,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
       return { ...message, status: terminalStatus, text, traceAutoLifecycle: "terminal", runnerTrace, error: error ?? message.error ?? null, agentRun: agentRun ?? undefined, updatedAt: new Date().toISOString() };
     });
     rememberTurnStatus(traceId, result);
+    markWorkbenchTraceProjected(traceId);
     void hydrateTraceEvents(messages.value);
     chatPending.value = false;
     currentRequest.value = null;
@@ -1069,6 +1086,7 @@ export const useWorkbenchStore = defineStore("workbench", () => {
     currentRequest.value = null;
     await refreshSelectedSessionStatus(conversation);
     await refreshConversations(conversation.conversationId);
+    finishWorkbenchSessionSwitchFullLoad(conversation.conversationId, selectedConversation ? "ok" : "partial");
     return true;
   }
 
diff --git a/web/hwlab-cloud-web/src/utils/workbench-performance.ts b/web/hwlab-cloud-web/src/utils/workbench-performance.ts
new file mode 100644
index 00000000..afdd3694
--- /dev/null
+++ b/web/hwlab-cloud-web/src/utils/workbench-performance.ts
@@ -0,0 +1,414 @@
+// SPEC: PJ2026-01060505 Workbench Performance draft-2026-06-17-p0
+// Browser-side Workbench journey probe. Prometheus label shaping is enforced again by cloud-api.
+
+import type { ChatMessage, TraceEvent } from "@/types";
+
+type WorkbenchEventKind = "workbench_journey" | "workbench_event_phase" | "workbench_backend_event_visible";
+type WorkbenchOutcome = "ok" | "timeout" | "error" | "dropped" | "stale" | "partial" | "empty" | "network" | "unknown";
+
+interface WorkbenchPerformanceEvent {
+  kind: WorkbenchEventKind;
+  valueMs: number;
+  route?: string;
+  journey?: string;
+  phase?: string;
+  eventType?: string;
+  backend?: string;
+  transport?: string;
+  entry?: string;
+  source?: string;
+  targetState?: string;
+  cache?: string;
+  authState?: string;
+  visibility?: string;
+  outcome?: WorkbenchOutcome;
+}
+
+interface OpenJourneyState {
+  startAt: number;
+  route: string;
+  cache: string;
+  authState: string;
+  firstVisibleReported: boolean;
+  fullLoadReported: boolean;
+}
+
+interface SessionSwitchState {
+  conversationId: string;
+  startAt: number;
+  route: string;
+  source: string;
+  targetState: string;
+  cache: string;
+  firstVisibleReported: boolean;
+  fullLoadReported: boolean;
+}
+
+interface SubmitJourneyState {
+  traceId: string;
+  conversationId: string;
+  startAt: number;
+  route: string;
+  entry: string;
+  backend: string;
+  transport: string;
+  firstVisibleReported: boolean;
+  apiAcceptedReported: boolean;
+}
+
+interface TraceEventState {
+  traceId: string;
+  receivedAt: number;
+  projectedAt: number | null;
+  eventCreatedAt: number | null;
+  eventType: string;
+  backend: string;
+  transport: string;
+  visibleReported: boolean;
+}
+
+const SCHEMA_VERSION = "hwlab-web-performance-v2";
+const FLUSH_INTERVAL_MS = 2500;
+const MAX_QUEUE = 120;
+const submitJourneys = new Map<string, SubmitJourneyState>();
+const sessionSwitches = new Map<string, SessionSwitchState>();
+const traceEvents = new Map<string, TraceEventState>();
+let openJourney: OpenJourneyState | null = null;
+let queue: WorkbenchPerformanceEvent[] = [];
+let installed = false;
+let flushTimer: number | null = null;
+
+export function startWorkbenchOpenJourney(input: { route?: string; cache?: "warm" | "cold" | "unknown"; authState?: "warm" | "login_redirect" | "unknown" } = {}): void {
+  ensureInstalled();
+  openJourney = {
+    startAt: monotonicNow(),
+    route: routeTemplate(input.route ?? pageRoute()),
+    cache: input.cache ?? "unknown",
+    authState: input.authState ?? "unknown",
+    firstVisibleReported: false,
+    fullLoadReported: false
+  };
+}
+
+export function finishWorkbenchOpenFullLoad(outcome: WorkbenchOutcome = "ok"): void {
+  if (!openJourney || openJourney.fullLoadReported) return;
+  openJourney.fullLoadReported = true;
+  enqueue({
+    kind: "workbench_journey",
+    journey: "workbench_open_full_load",
+    route: openJourney.route,
+    cache: openJourney.cache,
+    authState: openJourney.authState,
+    visibility: visibilityState(),
+    outcome,
+    valueMs: elapsedSince(openJourney.startAt)
+  });
+}
+
+export function startWorkbenchSessionSwitch(input: { conversationId: string | null | undefined; source: "rail" | "deeplink" | "history" | "direct"; targetState?: string | null; cache?: "warm" | "cold" | "unknown" }): void {
+  const conversationId = safeText(input.conversationId);
+  if (!conversationId) return;
+  ensureInstalled();
+  sessionSwitches.set(conversationId, {
+    conversationId,
+    startAt: monotonicNow(),
+    route: pageRoute(),
+    source: input.source,
+    targetState: normalizeTargetState(input.targetState),
+    cache: input.cache ?? "unknown",
+    firstVisibleReported: false,
+    fullLoadReported: false
+  });
+}
+
+export function finishWorkbenchSessionSwitchFullLoad(conversationId: string | null | undefined, outcome: WorkbenchOutcome = "ok"): void {
+  const state = sessionSwitches.get(safeText(conversationId));
+  if (!state || state.fullLoadReported) return;
+  state.fullLoadReported = true;
+  enqueue({
+    kind: "workbench_journey",
+    journey: "session_switch_full_load",
+    route: state.route,
+    source: state.source,
+    targetState: state.targetState,
+    cache: state.cache,
+    visibility: visibilityState(),
+    outcome,
+    valueMs: elapsedSince(state.startAt)
+  });
+}
+
+export function failWorkbenchSessionSwitch(conversationId: string | null | undefined): void {
+  finishWorkbenchSessionSwitchFullLoad(conversationId, "error");
+}
+
+export function startWorkbenchSubmitJourney(input: { traceId: string; conversationId: string; entry: "new" | "existing" | "steer" | "retry"; backend?: string | null; transport?: string | null }): void {
+  if (!input.traceId || !input.conversationId) return;
+  ensureInstalled();
+  submitJourneys.set(input.traceId, {
+    traceId: input.traceId,
+    conversationId: input.conversationId,
+    startAt: monotonicNow(),
+    route: pageRoute(),
+    entry: input.entry,
+    backend: normalizeBackend(input.backend),
+    transport: normalizeTransport(input.transport ?? "sse"),
+    firstVisibleReported: false,
+    apiAcceptedReported: false
+  });
+}
+
+export function markWorkbenchSubmitApiAccepted(traceId: string | null | undefined): void {
+  const state = submitJourneys.get(safeText(traceId));
+  if (!state || state.apiAcceptedReported) return;
+  state.apiAcceptedReported = true;
+  enqueue({
+    kind: "workbench_event_phase",
+    phase: "user_submit_to_api_accepted",
+    eventType: "request",
+    backend: state.backend,
+    transport: state.transport,
+    outcome: "ok",
+    valueMs: elapsedSince(state.startAt)
+  });
+}
+
+export function failWorkbenchSubmitJourney(traceId: string | null | undefined, outcome: WorkbenchOutcome = "error"): void {
+  const state = submitJourneys.get(safeText(traceId));
+  if (!state || state.firstVisibleReported) return;
+  state.firstVisibleReported = true;
+  enqueue({
+    kind: "workbench_journey",
+    journey: "submit_to_first_visible",
+    route: state.route,
+    entry: state.entry,
+    backend: state.backend,
+    transport: state.transport,
+    visibility: visibilityState(),
+    outcome,
+    valueMs: elapsedSince(state.startAt)
+  });
+  submitJourneys.delete(state.traceId);
+}
+
+export function markWorkbenchTraceEventsReceived(input: { traceId: string | null | undefined; events: TraceEvent[]; transport: "sse" | "rest_gap" | "poll" }): void {
+  const traceId = safeText(input.traceId);
+  if (!traceId) return;
+  const event = input.events.find(isUserVisibleTraceEvent) ?? input.events[0];
+  if (!event) return;
+  const eventType = eventTypeFromTraceEvent(event);
+  const backend = backendFromTraceEvent(event);
+  const eventCreatedAt = traceEventCreatedAt(event);
+  const receivedAt = monotonicNow();
+  traceEvents.set(traceId, { traceId, receivedAt, projectedAt: null, eventCreatedAt, eventType, backend, transport: input.transport, visibleReported: false });
+  if (eventCreatedAt !== null) {
+    enqueue({ kind: "workbench_event_phase", phase: "sse_to_receive", eventType, backend, transport: input.transport, outcome: "ok", valueMs: Math.max(0, wallNow() - eventCreatedAt) });
+  }
+}
+
+export function markWorkbenchTraceProjected(traceId: string | null | undefined): void {
+  const state = traceEvents.get(safeText(traceId));
+  if (!state || state.projectedAt !== null) return;
+  const projectedAt = monotonicNow();
+  state.projectedAt = projectedAt;
+  enqueue({ kind: "workbench_event_phase", phase: "receive_to_project", eventType: state.eventType, backend: state.backend, transport: state.transport, outcome: "ok", valueMs: Math.max(0, projectedAt - state.receivedAt) });
+}
+
+export function acknowledgeWorkbenchVisibleAfterPaint(input: { messages: ChatMessage[]; activeConversationId?: string | null; detailLoading?: boolean }): void {
+  afterNextPaint(() => acknowledgeWorkbenchVisible(input));
+}
+
+export function acknowledgeWorkbenchVisible(input: { messages: ChatMessage[]; activeConversationId?: string | null; detailLoading?: boolean }): void {
+  const now = monotonicNow();
+  const route = pageRoute();
+  if (openJourney && !openJourney.firstVisibleReported) {
+    openJourney.firstVisibleReported = true;
+    enqueue({ kind: "workbench_journey", journey: "workbench_open_first_visible", route: openJourney.route || route, cache: openJourney.cache, authState: openJourney.authState, visibility: visibilityState(), outcome: "ok", valueMs: Math.max(0, now - openJourney.startAt) });
+  }
+  const activeConversationId = safeText(input.activeConversationId);
+  const session = activeConversationId ? sessionSwitches.get(activeConversationId) : null;
+  if (session && !session.firstVisibleReported && !input.detailLoading) {
+    session.firstVisibleReported = true;
+    enqueue({ kind: "workbench_journey", journey: "session_switch_first_visible", route: session.route, source: session.source, targetState: session.targetState, cache: session.cache, visibility: visibilityState(), outcome: input.messages.length > 0 ? "ok" : "empty", valueMs: Math.max(0, now - session.startAt) });
+  }
+  for (const message of input.messages) {
+    const traceId = safeText(message.traceId ?? message.runnerTrace?.traceId);
+    if (!traceId || message.role !== "agent" || !isVisibleAgentMessage(message)) continue;
+    const submit = submitJourneys.get(traceId);
+    if (submit && !submit.firstVisibleReported) {
+      submit.firstVisibleReported = true;
+      enqueue({ kind: "workbench_journey", journey: "submit_to_first_visible", route: submit.route, entry: submit.entry, backend: submit.backend, transport: submit.transport, visibility: visibilityState(), outcome: "ok", valueMs: Math.max(0, now - submit.startAt) });
+      submitJourneys.delete(traceId);
+    }
+    const event = traceEvents.get(traceId);
+    if (event && !event.visibleReported) {
+      event.visibleReported = true;
+      if (event.projectedAt !== null) enqueue({ kind: "workbench_event_phase", phase: "project_to_paint", eventType: event.eventType, backend: event.backend, transport: event.transport, outcome: "ok", valueMs: Math.max(0, now - event.projectedAt) });
+      if (event.eventCreatedAt !== null) enqueue({ kind: "workbench_backend_event_visible", eventType: event.eventType, backend: event.backend, transport: event.transport, outcome: "ok", valueMs: Math.max(0, wallNow() - event.eventCreatedAt) });
+      traceEvents.delete(traceId);
+    }
+  }
+}
+
+export function resetWorkbenchPerformanceForTest(): void {
+  submitJourneys.clear();
+  sessionSwitches.clear();
+  traceEvents.clear();
+  openJourney = null;
+  queue = [];
+  if (flushTimer !== null && typeof window !== "undefined") window.clearTimeout(flushTimer);
+  flushTimer = null;
+  installed = false;
+}
+
+export function drainWorkbenchPerformanceEventsForTest(): WorkbenchPerformanceEvent[] {
+  const events = queue;
+  queue = [];
+  return events;
+}
+
+function enqueue(event: WorkbenchPerformanceEvent): void {
+  if (!Number.isFinite(event.valueMs) || event.valueMs < 0) return;
+  queue.push({ ...event, valueMs: Math.round(event.valueMs * 1000) / 1000 });
+  if (queue.length > MAX_QUEUE) queue.splice(0, queue.length - MAX_QUEUE);
+  scheduleFlush();
+}
+
+function scheduleFlush(): void {
+  if (typeof window === "undefined" || flushTimer !== null) return;
+  flushTimer = window.setTimeout(() => flushWorkbenchPerformance(false), FLUSH_INTERVAL_MS);
+}
+
+function flushWorkbenchPerformance(useBeacon: boolean): void {
+  if (flushTimer !== null && typeof window !== "undefined") {
+    window.clearTimeout(flushTimer);
+    flushTimer = null;
+  }
+  if (!queue.length || typeof window === "undefined") return;
+  const events = queue.splice(0, queue.length);
+  const body = JSON.stringify({ schemaVersion: SCHEMA_VERSION, serviceId: "hwlab-cloud-web", page: pageRoute(), events });
+  if (useBeacon && navigator.sendBeacon) {
+    navigator.sendBeacon("/v1/web-performance", new Blob([body], { type: "application/json" }));
+    return;
+  }
+  void fetch("/v1/web-performance", { method: "POST", headers: { "content-type": "application/json" }, body, credentials: "same-origin", keepalive: true }).catch(() => undefined);
+}
+
+function ensureInstalled(): void {
+  if (installed || typeof document === "undefined") return;
+  installed = true;
+  document.addEventListener("visibilitychange", () => {
+    if (document.visibilityState === "hidden") flushWorkbenchPerformance(true);
+  });
+}
+
+function afterNextPaint(callback: () => void): void {
+  if (typeof requestAnimationFrame !== "function") {
+    callback();
+    return;
+  }
+  requestAnimationFrame(() => requestAnimationFrame(callback));
+}
+
+function isVisibleAgentMessage(message: ChatMessage): boolean {
+  if (message.runnerTrace && ((message.runnerTrace.events?.length ?? 0) > 0 || message.runnerTrace.eventCount)) return true;
+  if (String(message.text ?? "").trim()) return true;
+  return !["pending", "running"].includes(String(message.status ?? "").toLowerCase());
+}
+
+function isUserVisibleTraceEvent(event: TraceEvent): boolean {
+  const type = eventTypeFromTraceEvent(event);
+  return type === "assistant" || type === "tool_call" || type === "backend" || type === "terminal" || type === "error";
+}
+
+function eventTypeFromTraceEvent(event: TraceEvent | null | undefined): string {
+  const raw = safeText(event?.type ?? event?.kind ?? event?.label ?? event?.status).toLowerCase();
+  if (/tool/u.test(raw)) return "tool_call";
+  if (/assistant|message|delta|reply/u.test(raw)) return "assistant";
+  if (/terminal|complete|final/u.test(raw)) return "terminal";
+  if (/error|fail|timeout/u.test(raw)) return "error";
+  if (/backend|runner|agentrun/u.test(raw)) return "backend";
+  if (/request|accepted/u.test(raw)) return "request";
+  return "status";
+}
+
+function backendFromTraceEvent(event: TraceEvent | null | undefined): string {
+  const direct = safeText(event?.backend ?? event?.backendProfile ?? event?.provider ?? event?.runnerKind);
+  return normalizeBackend(direct);
+}
+
+function normalizeBackend(value: unknown): string {
+  const text = safeText(value).toLowerCase();
+  if (!text) return "unknown";
+  if (text.includes("/")) return text;
+  if (/^(?:codex|deepseek|openai|claude|hyue)/u.test(text)) return `agentrun-v01/${text}`;
+  return text;
+}
+
+function normalizeTransport(value: unknown): string {
+  const text = safeText(value).toLowerCase();
+  return text === "rest_gap" || text === "poll" || text === "sse" ? text : "unknown";
+}
+
+function normalizeTargetState(value: unknown): string {
+  const text = safeText(value).toLowerCase();
+  if (text === "running" || text === "terminal" || text === "empty") return text;
+  if (["completed", "failed", "timeout", "canceled"].includes(text)) return "terminal";
+  return "unknown";
+}
+
+function traceEventCreatedAt(event: TraceEvent): number | null {
+  const raw = safeText(event.createdAt ?? event.ts ?? event.timestamp);
+  const parsed = raw ? Date.parse(raw) : NaN;
+  return Number.isFinite(parsed) ? parsed : null;
+}
+
+function pageRoute(): string {
+  if (typeof window === "undefined") return "/workbench";
+  return routeTemplate(`${window.location.pathname}${window.location.hash || ""}` || "/workbench");
+}
+
+function routeTemplate(input: string): string {
+  const raw = safeText(input) || "/workbench";
+  const pathOnly = raw.startsWith("#") ? raw.slice(1) || "/" : raw.split(/[?#]/u, 1)[0] || "/";
+  const segments = pathOnly.split("/").filter(Boolean).map((part) => routeSegmentTemplate(part));
+  return `/${segments.join("/")}`;
+}
+
+function routeSegmentTemplate(segment: string): string {
+  const decoded = safeDecode(segment);
+  if (/^(?:trc|trace|thread|run|cmd|job|ses|cnv|conv|gws|box|res|pod|dp|usr)[_-]/iu.test(decoded)) return ":id";
+  if (/^[0-9a-f]{8,}(?:-[0-9a-f]{4,}){2,}$/iu.test(decoded)) return ":uuid";
+  if (/^[A-Za-z0-9_-]{20,}$/u.test(decoded)) return ":id";
+  if (/^\d{5,}$/u.test(decoded)) return ":id";
+  return decoded.replace(/[^A-Za-z0-9_.:-]/gu, "_").slice(0, 80) || "_";
+}
+
+function safeDecode(value: string): string {
+  try {
+    return decodeURIComponent(value);
+  } catch {
+    return value;
+  }
+}
+
+function visibilityState(): string {
+  if (typeof document === "undefined") return "unknown";
+  return document.visibilityState === "hidden" ? "background" : "foreground";
+}
+
+function monotonicNow(): number {
+  return typeof performance !== "undefined" && typeof performance.now === "function" ? performance.now() : Date.now();
+}
+
+function wallNow(): number {
+  return Date.now();
+}
+
+function elapsedSince(startAt: number): number {
+  return Math.max(0, monotonicNow() - startAt);
+}
+
+function safeText(value: unknown): string {
+  return typeof value === "string" ? value.trim() : "";
+}
diff --git a/web/hwlab-cloud-web/src/views/workbench/CodeWorkbenchView.vue b/web/hwlab-cloud-web/src/views/workbench/CodeWorkbenchView.vue
index 051fc137..65f9cef8 100644
--- a/web/hwlab-cloud-web/src/views/workbench/CodeWorkbenchView.vue
+++ b/web/hwlab-cloud-web/src/views/workbench/CodeWorkbenchView.vue
@@ -1,4 +1,7 @@
 <script setup lang="ts">
+// SPEC: PJ2026-01060505 Workbench Performance draft-2026-06-17-p0
+// Starts Workbench first-screen journey timing around route hydrate.
+
 import { computed, onBeforeUnmount, onMounted, ref, watch } from "vue";
 import { useRoute, useRouter } from "vue-router";
 import CommandComposer from "@/components/workbench/CommandComposer.vue";
@@ -9,6 +12,7 @@ import { useAutoRefresh } from "@/composables/useAutoRefresh";
 import { shouldReflectWorkbenchConversationUrl } from "@/router/workbench-navigation";
 import { useWorkbenchStore } from "@/stores/workbench";
 import { DEFAULT_WORKBENCH_PROJECT_ID, normalizeWorkbenchConversationId, normalizeWorkbenchProjectId } from "@/utils";
+import { finishWorkbenchOpenFullLoad, startWorkbenchOpenJourney } from "@/utils/workbench-performance";
 
 const workbench = useWorkbenchStore();
 const route = useRoute();
@@ -20,9 +24,11 @@ const componentActive = ref(false);
 onMounted(async () => {
   componentActive.value = true;
   applyingRouteConversation.value = Boolean(routeConversationId.value);
+  startWorkbenchOpenJourney({ route: route.path, cache: routeConversationId.value ? "cold" : "warm", authState: "warm" });
   try {
     await workbench.hydrate({ conversationId: routeConversationId.value });
     await applyRouteConversation();
+    finishWorkbenchOpenFullLoad(workbench.error ? "error" : "ok");
   } finally {
     applyingRouteConversation.value = false;
   }