diff --git a/docs/release-control/v6/internal/subsystems/performance-and-scalability.md b/docs/release-control/v6/internal/subsystems/performance-and-scalability.md
index 157acbbb5..0037bff18 100644
--- a/docs/release-control/v6/internal/subsystems/performance-and-scalability.md
+++ b/docs/release-control/v6/internal/subsystems/performance-and-scalability.md
@@ -703,7 +703,9 @@ change may globally weaken the Task 03 lifecycle-state idempotency invariant.
     accumulating, but it must never be expanded into synthetic timestamps or a
     flat line. Fewer than two stored points remains `Collecting history` and
     only metrics-store samples may contribute chart geometry, bounds, or hover
-    inspection.
+    inspection. Current-value legends must preserve the same availability
+    semantics as workload rows: the poller's negative unknown-disk sentinel is
+    unavailable and renders `-`, never a fabricated negative percentage.
     History cards must let the plot area stretch to the card height instead of
     pinning the SVG wrapper to a fixed short height, so guest and node drawer
     history cards do not leave unused card space when headers have different
diff --git a/frontend-modern/browser-verification.json b/frontend-modern/browser-verification.json
index 82e026017..26615cc2e 100644
--- a/frontend-modern/browser-verification.json
+++ b/frontend-modern/browser-verification.json
@@ -1,30 +1,35 @@
 {
   "version": 1,
-  "base_sha": "caf7f80867871f0a601d9a572cbab309f8d4b41f",
-  "verified_at": "2026-08-25T18:42:00Z",
+  "base_sha": "3678d583bf43840d0086e4ba70c81aec77dadd01",
+  "verified_at": "2026-08-25T19:06:05Z",
   "result": "passed",
   "changed_paths": [
-    "frontend-modern/src/components/AI/AICostDashboard.tsx",
-    "frontend-modern/src/utils/aiCostPresentation.ts"
+    "frontend-modern/src/components/Workloads/guestDrawerModel.ts"
   ],
   "content_sha256": {
-    "frontend-modern/src/components/AI/AICostDashboard.tsx": "eb9291049d9c415bfc24868cf45da5f9d862bb24f98100bc0fb10e2188554100",
-    "frontend-modern/src/utils/aiCostPresentation.ts": "816376697dc3eefa1b3d3a198ab29f80ae9148ddbffaf3dc1ab18fb22bc46041"
+    "frontend-modern/src/components/Workloads/guestDrawerModel.ts": "5aaccadfaa746f391431c5138e7a1c051b643e264e57fb8e2f58f121cffb0de9"
   },
-  "routes": ["/settings/pulse-intelligence/provider"],
+  "routes": [
+    "/proxmox/overview",
+    "/docker/overview",
+    "/kubernetes/overview",
+    "/truenas/apps"
+  ],
   "viewports": [
-    { "width": 1440, "height": 900 },
+    { "width": 1280, "height": 800 },
     { "width": 390, "height": 844 }
   ],
   "states": [
-    "loaded provider usage range with no provider/model rows",
-    "phone projection retaining Provider, Model, and Est. USD",
-    "desktop projection restoring Input, Output, and Total"
+    "stopped Proxmox guest History drawer using the negative unknown-disk sentinel",
+    "running Docker container History drawer with populated utilization data",
+    "degraded Kubernetes pod History drawer with populated utilization and network data",
+    "TrueNAS app Overview drawer with long container and identity values"
   ],
   "interactions": [
-    "navigated to Provider & Models and scrolled the settings surface to Provider Usage & Spend",
-    "verified the empty-state row is fully readable at 390px after correcting fixed-table text clipping",
-    "measured zero table-shell and page overflow at 390px and 1440px",
-    "confirmed all six desktop headers return at 1440px"
+    "opened the stopped dev-portal Proxmox guest and switched from Overview to History at 390px",
+    "verified the unavailable disk fallback renders as a dash instead of a negative percentage at 390px and 1280px",
+    "opened Docker and Kubernetes History tabs to confirm valid current metrics and chart geometry remain intact",
+    "opened a TrueNAS app drawer and inspected long-value truncation, stacking, scrolling, and tab placement",
+    "restored the browser viewport after responsive verification"
   ]
 }
diff --git a/frontend-modern/src/components/Workloads/GuestDrawer.test.tsx b/frontend-modern/src/components/Workloads/GuestDrawer.test.tsx
index acc35dab5..4fea39bfc 100644
--- a/frontend-modern/src/components/Workloads/GuestDrawer.test.tsx
+++ b/frontend-modern/src/components/Workloads/GuestDrawer.test.tsx
@@ -502,6 +502,33 @@ describe('GuestDrawer', () => {
       expect(utilizationChart.querySelector('path')).toBeNull();
     });
 
+    it('renders unavailable current disk usage as a dash', async () => {
+      chartsApiMocks.getMetricsHistory.mockResolvedValue({
+        resourceType: 'vm',
+        resourceId: 'inst1:node1:100',
+        range: '24h',
+        start: 0,
+        end: 0,
+        metrics: {},
+        source: 'store',
+      });
+      render(() => (
+        <GuestDrawer
+          guest={makeGuest({
+            disk: { total: 100, used: 0, free: 100, usage: -1 },
+          })}
+          onClose={vi.fn()}
+        />
+      ));
+
+      await fireEvent.click(screen.getByText('History'));
+      await waitFor(() => expect(chartsApiMocks.getMetricsHistory).toHaveBeenCalled());
+
+      const utilizationChart = screen.getAllByTestId('guest-history-group-chart')[0];
+      expect(utilizationChart).toHaveTextContent('Disk-');
+      expect(utilizationChart).not.toHaveTextContent('Disk-100.0%');
+    });
+
     it('updates grouped metric header values on History chart hover', async () => {
       render(() => <GuestDrawer guest={makeGuest()} onClose={vi.fn()} />);
 
diff --git a/frontend-modern/src/components/Workloads/__tests__/guestDrawerModel.branchcov2.test.ts b/frontend-modern/src/components/Workloads/__tests__/guestDrawerModel.branchcov2.test.ts
index 66eec4cbd..f4e5d9bf9 100644
--- a/frontend-modern/src/components/Workloads/__tests__/guestDrawerModel.branchcov2.test.ts
+++ b/frontend-modern/src/components/Workloads/__tests__/guestDrawerModel.branchcov2.test.ts
@@ -142,6 +142,15 @@ describe('guestDrawerModel (branch coverage)', () => {
       expect(result.memory).toBeUndefined();
     });
 
+    it('does not render the negative unknown-disk sentinel as a current history value', () => {
+      const result = getGuestDrawerCurrentMetrics(
+        makeGuest({
+          disk: { total: 100, used: 0, free: 100, usage: -1 },
+        }),
+      );
+      expect(result.disk).toBeUndefined();
+    });
+
     it('drops a non-finite network value via the finite() guard', () => {
       const result = getGuestDrawerCurrentMetrics(
         makeGuest({ networkIn: Number.POSITIVE_INFINITY }),
diff --git a/frontend-modern/src/components/Workloads/guestDrawerModel.ts b/frontend-modern/src/components/Workloads/guestDrawerModel.ts
index 7f9aa8595..766c563e3 100644
--- a/frontend-modern/src/components/Workloads/guestDrawerModel.ts
+++ b/frontend-modern/src/components/Workloads/guestDrawerModel.ts
@@ -73,13 +73,19 @@ export const getGuestDrawerCurrentMetrics = (guest: Guest): Record<string, numbe
   const cpuPercent = available('cpu') ? getWorkloadCPUPercent(guest.cpu) : undefined;
   const memUsage =
     available('memory') && !guest.memory?.usageUnavailable ? guest.memory?.usage : undefined;
-  const diskUsage = available('disk') ? guest.disk?.usage : undefined;
+  const reportedDiskUsage = available('disk') ? guest.disk?.usage : undefined;
+  const diskUsage =
+    typeof reportedDiskUsage === 'number' &&
+    Number.isFinite(reportedDiskUsage) &&
+    reportedDiskUsage >= 0
+      ? reportedDiskUsage
+      : undefined;
   const finite = (value: number | undefined): number | undefined =>
     typeof value === 'number' && Number.isFinite(value) ? value : undefined;
   return {
     cpu: finite(cpuPercent),
     memory: finite(memUsage),
-    disk: finite(diskUsage),
+    disk: diskUsage,
     netin: available('networkIO') ? finite(guest.networkIn) : undefined,
     netout: available('networkIO') ? finite(guest.networkOut) : undefined,
     diskread: available('diskIO') ? finite(guest.diskRead) : undefined,