diff --git a/inspect-ui/src/__tests__/api.test.ts b/inspect-ui/src/__tests__/api.test.ts
new file mode 100644
index 0000000..13af2a3
--- /dev/null
+++ b/inspect-ui/src/__tests__/api.test.ts
@@ -0,0 +1,21 @@
+import { describe, it, expect } from "bun:test";
+import { htmlUrl, screenshotUrl } from "../api";
+
+describe("htmlUrl", () => {
+  it("encodes runId and name", () => {
+    expect(htmlUrl("run-1", "step-00001.html")).toBe(
+      "/api/runs/run-1/html/step-00001.html",
+    );
+    expect(htmlUrl("run with spaces", "after step.html")).toBe(
+      "/api/runs/run%20with%20spaces/html/after%20step.html",
+    );
+  });
+});
+
+describe("screenshotUrl", () => {
+  it("encodes runId and name", () => {
+    expect(screenshotUrl("run-1", "step-00001.png")).toBe(
+      "/api/runs/run-1/screenshots/step-00001.png",
+    );
+  });
+});
diff --git a/inspect-ui/src/api.ts b/inspect-ui/src/api.ts
index ba1e97a..5db5695 100644
--- a/inspect-ui/src/api.ts
+++ b/inspect-ui/src/api.ts
@@ -23,3 +23,7 @@ export function getStep(runId: string, index: number): Promise<Step> {
 export function screenshotUrl(runId: string, name: string): string {
   return `/api/runs/${encodeURIComponent(runId)}/screenshots/${encodeURIComponent(name)}`;
 }
+
+export function htmlUrl(runId: string, name: string): string {
+  return `/api/runs/${encodeURIComponent(runId)}/html/${encodeURIComponent(name)}`;
+}
diff --git a/inspect-ui/src/panels/HierarchyPanel.css b/inspect-ui/src/panels/HierarchyPanel.css
new file mode 100644
index 0000000..2acdbd1
--- /dev/null
+++ b/inspect-ui/src/panels/HierarchyPanel.css
@@ -0,0 +1,83 @@
+.hierarchy-panel {
+  display: flex;
+  flex-direction: column;
+  gap: 8px;
+  font-family: var(--font-mono);
+  font-size: 12px;
+  color: var(--text-primary);
+}
+
+.hierarchy-filter {
+  font-family: var(--font-mono);
+  font-size: 12px;
+  padding: 4px 8px;
+  border: 1px solid var(--border);
+  background: var(--surface-1);
+  color: var(--text-primary);
+}
+
+.hierarchy-table-wrap {
+  overflow: auto;
+  max-height: 480px;
+  border: 1px solid var(--border);
+}
+
+.hierarchy-table {
+  width: 100%;
+  border-collapse: collapse;
+}
+
+.hierarchy-table th {
+  position: sticky;
+  top: 0;
+  background: var(--surface-1);
+  text-align: left;
+  padding: 4px 8px;
+  font-weight: normal;
+  color: var(--text-secondary);
+  border-bottom: 1px solid var(--border);
+}
+
+.hierarchy-table td {
+  padding: 2px 8px;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  border-bottom: 1px solid var(--border-subtle, var(--border));
+}
+
+.hierarchy-table tr:hover td {
+  background: var(--surface-2, transparent);
+}
+
+.hierarchy-tag {
+  color: var(--text-secondary);
+  max-width: 140px;
+}
+
+.hierarchy-id {
+  color: var(--text-primary);
+  max-width: 160px;
+}
+
+.hierarchy-text {
+  max-width: 320px;
+  color: var(--text-primary);
+}
+
+.hierarchy-bounds {
+  color: var(--text-secondary);
+  text-align: right;
+}
+
+.hierarchy-empty {
+  font-family: var(--font-mono);
+  font-size: 12px;
+  color: var(--text-secondary);
+  padding: 16px;
+}
+
+.hierarchy-count {
+  color: var(--text-secondary);
+  font-size: 11px;
+}
diff --git a/inspect-ui/src/panels/HierarchyPanel.tsx b/inspect-ui/src/panels/HierarchyPanel.tsx
new file mode 100644
index 0000000..aceed5d
--- /dev/null
+++ b/inspect-ui/src/panels/HierarchyPanel.tsx
@@ -0,0 +1,89 @@
+import { useMemo, useState } from "react";
+import type { HierarchyElement, Hierarchy } from "../types";
+import "./HierarchyPanel.css";
+
+interface HierarchyPanelProps {
+  hierarchy?: Hierarchy;
+}
+
+export default function HierarchyPanel({ hierarchy }: HierarchyPanelProps): JSX.Element {
+  const [filter, setFilter] = useState("");
+  const elements = hierarchy?.elements ?? [];
+
+  const rows = useMemo(() => {
+    const lower = filter.trim().toLowerCase();
+    if (!lower) return elements;
+    return elements.filter((element) => matches(element, lower));
+  }, [elements, filter]);
+
+  if (elements.length === 0) {
+    return <div className="hierarchy-empty">no hierarchy captured</div>;
+  }
+
+  return (
+    <div className="hierarchy-panel">
+      <input
+        type="text"
+        className="hierarchy-filter"
+        placeholder="filter by id, text, desc, class, tag..."
+        value={filter}
+        onChange={(e) => setFilter(e.target.value)}
+      />
+      <div className="hierarchy-table-wrap">
+        <table className="hierarchy-table">
+          <thead>
+            <tr>
+              <th>tag/class</th>
+              <th>id</th>
+              <th>text/desc</th>
+              <th>bounds</th>
+            </tr>
+          </thead>
+          <tbody>
+            {rows.map((element, index) => (
+              <HierarchyRow key={index} element={element} />
+            ))}
+          </tbody>
+        </table>
+      </div>
+      <div className="hierarchy-count">
+        {rows.length} of {elements.length}
+      </div>
+    </div>
+  );
+}
+
+function HierarchyRow({ element }: { element: HierarchyElement }): JSX.Element {
+  const tag = element.tag ?? element.class ?? "";
+  const text = (element.text ?? element.description ?? "").slice(0, 80);
+  const bounds = element.bounds;
+  return (
+    <tr>
+      <td className="hierarchy-tag">{tag}</td>
+      <td className="hierarchy-id">{element.resourceId ?? ""}</td>
+      <td className="hierarchy-text">{text}</td>
+      <td className="hierarchy-bounds">
+        [{bounds.left},{bounds.top},{bounds.right},{bounds.bottom}]
+      </td>
+    </tr>
+  );
+}
+
+function matches(element: HierarchyElement, needle: string): boolean {
+  const fields = [
+    element.resourceId,
+    element.text,
+    element.description,
+    element.class,
+    element.tag,
+  ];
+  for (const value of fields) {
+    if (value && value.toLowerCase().includes(needle)) return true;
+  }
+  if (element.attributes) {
+    for (const value of Object.values(element.attributes)) {
+      if (value.toLowerCase().includes(needle)) return true;
+    }
+  }
+  return false;
+}
diff --git a/inspect-ui/src/panels/HtmlPanel.css b/inspect-ui/src/panels/HtmlPanel.css
new file mode 100644
index 0000000..7e94687
--- /dev/null
+++ b/inspect-ui/src/panels/HtmlPanel.css
@@ -0,0 +1,60 @@
+.html-panel {
+  display: flex;
+  flex-direction: column;
+  gap: 8px;
+}
+
+.html-toolbar {
+  display: flex;
+  gap: 4px;
+}
+
+.html-tab {
+  font-family: var(--font-mono);
+  font-size: 12px;
+  padding: 2px 10px;
+  background: var(--surface-1);
+  border: 1px solid var(--border);
+  color: var(--text-secondary);
+  cursor: pointer;
+}
+
+.html-tab-active {
+  color: var(--text-primary);
+  border-color: var(--border-strong, var(--border));
+}
+
+.html-frame {
+  width: 100%;
+  height: 480px;
+  border: 1px solid var(--border);
+  background: white;
+}
+
+.html-source {
+  font-family: var(--font-mono);
+  font-size: 11px;
+  color: var(--text-primary);
+  background: var(--surface-1);
+  border: 1px solid var(--border);
+  padding: 8px;
+  margin: 0;
+  max-height: 480px;
+  overflow: auto;
+  white-space: pre-wrap;
+  word-break: break-all;
+}
+
+.html-empty {
+  font-family: var(--font-mono);
+  font-size: 12px;
+  color: var(--text-secondary);
+  padding: 16px;
+}
+
+.html-error {
+  font-family: var(--font-mono);
+  font-size: 12px;
+  color: var(--text-violation, #c33);
+  padding: 16px;
+}
diff --git a/inspect-ui/src/panels/HtmlPanel.tsx b/inspect-ui/src/panels/HtmlPanel.tsx
new file mode 100644
index 0000000..5155a6c
--- /dev/null
+++ b/inspect-ui/src/panels/HtmlPanel.tsx
@@ -0,0 +1,73 @@
+import { useEffect, useState } from "react";
+import { htmlUrl } from "../api";
+import "./HtmlPanel.css";
+
+interface HtmlPanelProps {
+  runId: string;
+  fileName: string;
+  available: boolean;
+}
+
+type ViewMode = "render" | "source";
+
+export default function HtmlPanel({ runId, fileName, available }: HtmlPanelProps): JSX.Element {
+  const [mode, setMode] = useState<ViewMode>("render");
+  const [source, setSource] = useState<string | null>(null);
+  const [error, setError] = useState<string | null>(null);
+  const url = htmlUrl(runId, fileName);
+
+  useEffect(() => {
+    if (!available || mode !== "source") return;
+    let cancelled = false;
+    setSource(null);
+    setError(null);
+    fetch(url)
+      .then((response) => {
+        if (!response.ok) throw new Error(`${response.status} ${response.statusText}`);
+        return response.text();
+      })
+      .then((text) => {
+        if (!cancelled) setSource(text);
+      })
+      .catch((failure: unknown) => {
+        if (!cancelled) setError(failure instanceof Error ? failure.message : String(failure));
+      });
+    return () => {
+      cancelled = true;
+    };
+  }, [available, mode, url]);
+
+  if (!available) {
+    return <div className="html-empty">no html captured for this step</div>;
+  }
+
+  return (
+    <div className="html-panel">
+      <div className="html-toolbar">
+        <button
+          type="button"
+          className={mode === "render" ? "html-tab html-tab-active" : "html-tab"}
+          onClick={() => setMode("render")}
+        >
+          render
+        </button>
+        <button
+          type="button"
+          className={mode === "source" ? "html-tab html-tab-active" : "html-tab"}
+          onClick={() => setMode("source")}
+        >
+          source
+        </button>
+      </div>
+      {mode === "render" ? (
+        <iframe className="html-frame" src={url} sandbox="" title={fileName} />
+      ) : error ? (
+        <div className="html-error">failed to load: {error}</div>
+      ) : source === null ? (
+        <div className="html-empty">loading...</div>
+      ) : (
+        <pre className="html-source">{source}</pre>
+      )}
+    </div>
+  );
+}
diff --git a/inspect-ui/src/routes/RunDetail.tsx b/inspect-ui/src/routes/RunDetail.tsx
index 39a08fb..f13a525 100644
--- a/inspect-ui/src/routes/RunDetail.tsx
+++ b/inspect-ui/src/routes/RunDetail.tsx
@@ -3,6 +3,8 @@ import { Link } from "react-router-dom";
 import { getRun, getStep, screenshotUrl } from "../api";
 import type { Run, Step } from "../types";
 import ActionList from "../panels/ActionList";
+import HierarchyPanel from "../panels/HierarchyPanel";
+import HtmlPanel from "../panels/HtmlPanel";
 import Screenshot from "../panels/Screenshot";
 import SnapshotTable from "../panels/SnapshotTable";
 import ViolationsPanel from "../panels/ViolationsPanel";
@@ -135,6 +137,26 @@ export default function RunDetail() {
         />
       ),
     },
+    {
+      id: "hierarchy",
+      label: "Hierarchy",
+      content: <HierarchyPanel hierarchy={currentStep?.hierarchy} />,
+    },
+    ...(runId && currentStep?.html_available
+      ? [
+          {
+            id: "html",
+            label: "HTML",
+            content: (
+              <HtmlPanel
+                runId={runId}
+                fileName={`step-${String(currentStep.step).padStart(5, "0")}.html`}
+                available
+              />
+            ),
+          } satisfies TabDefinition,
+        ]
+      : []),
     {
       id: "properties",
       label: "Properties",
@@ -186,6 +208,26 @@ export default function RunDetail() {
         />
       ),
     },
+    {
+      id: "hierarchy",
+      label: "Hierarchy",
+      content: <HierarchyPanel hierarchy={nextStep?.hierarchy ?? currentStep?.hierarchy} />,
+    },
+    ...(runId && currentStep?.html_available
+      ? [
+          {
+            id: "html",
+            label: "HTML",
+            content: (
+              <HtmlPanel
+                runId={runId}
+                fileName={`step-${String(currentStep.step).padStart(5, "0")}-after.html`}
+                available
+              />
+            ),
+          } satisfies TabDefinition,
+        ]
+      : []),
     {
       id: "properties",
       label: "Properties",
diff --git a/inspect-ui/src/types.ts b/inspect-ui/src/types.ts
index 85af7c3..93aae47 100644
--- a/inspect-ui/src/types.ts
+++ b/inspect-ui/src/types.ts
@@ -50,6 +50,7 @@ export interface HierarchyElement {
   text?: string;
   description?: string;
   class?: string;
+  tag?: string;
   package?: string;
   clickable?: boolean;
   enabled?: boolean;
@@ -57,6 +58,7 @@ export interface HierarchyElement {
   focused?: boolean;
   selected?: boolean;
   bounds: BoundsRect;
+  attributes?: Record<string, string>;
 }
 
 export interface Hierarchy {
@@ -124,4 +126,5 @@ export interface Step {
   hierarchy?: Hierarchy;
   residuals?: Record<string, ResidualNode>;
   metrics?: Metrics;
+  html_available?: boolean;
 }