diff --git a/frontend/src/pages/AccountSettingsPage.tsx b/frontend/src/pages/AccountSettingsPage.tsx
index fe8ecffc..1037ba0f 100644
--- a/frontend/src/pages/AccountSettingsPage.tsx
+++ b/frontend/src/pages/AccountSettingsPage.tsx
@@ -18,6 +18,7 @@ import {
   RefreshCw,
   Server,
   Shield,
+  Wand2,
   UserCog,
   X,
 } from 'lucide-react'
@@ -662,6 +663,12 @@ export function AccountSettingsPage() {
                 title="Team categories"
                 description="Shared flow categories for your workspace"
               />
+              <SettingsRow
+                to="/account/l1-categories"
+                icon={<Wand2 className="h-4 w-4" />}
+                title="L1 AI build categories"
+                description="Which problem types the L1 assistant may build trees for"
+              />
               <SettingsRow
                 to="/account/target-lists"
                 icon={<Server className="h-4 w-4" />}
diff --git a/frontend/src/pages/account/L1CategoriesPage.tsx b/frontend/src/pages/account/L1CategoriesPage.tsx
new file mode 100644
index 00000000..ca923d2e
--- /dev/null
+++ b/frontend/src/pages/account/L1CategoriesPage.tsx
@@ -0,0 +1,98 @@
+import { useEffect, useState } from 'react'
+import { PageMeta } from '@/components/common/PageMeta'
+import { l1Api } from '@/api/l1'
+import { toast } from '@/lib/toast'
+import type { L1Categories } from '@/types/l1'
+
+const prettify = (key: string) =>
+  key.replace(/_/g, ' ').replace(/\b\w/g, (c) => c.toUpperCase())
+
+export default function L1CategoriesPage() {
+  const [data, setData] = useState<L1Categories | null>(null)
+  const [saving, setSaving] = useState<string | null>(null)
+
+  useEffect(() => {
+    l1Api
+      .getCategories()
+      .then(setData)
+      .catch(() => toast.error('Failed to load L1 categories.'))
+  }, [])
+
+  const toggle = async (cat: string) => {
+    if (!data) return
+    const next = data.enabled.includes(cat)
+      ? data.enabled.filter((c) => c !== cat)
+      : [...data.enabled, cat]
+    setSaving(cat)
+    try {
+      const updated = await l1Api.setCategories(next)
+      setData({ ...data, enabled: updated.enabled })
+      toast.success('L1 categories updated.')
+    } catch {
+      toast.error('Could not update categories.')
+    } finally {
+      setSaving(null)
+    }
+  }
+
+  if (!data) {
+    return (
+      <div className="max-w-2xl">
+        <PageMeta title="L1 AI Build Categories" />
+        <p className="text-sm text-muted-foreground">Loading…</p>
+      </div>
+    )
+  }
+
+  return (
+    <div className="max-w-2xl space-y-6">
+      <PageMeta title="L1 AI Build Categories" />
+      <div>
+        <h1 className="font-heading text-2xl font-bold text-heading">
+          L1 AI build categories
+        </h1>
+        <p className="mt-2 text-sm text-muted-foreground">
+          When an L1 tech describes a problem with no matching published flow, the
+          assistant can build a troubleshooting tree on the fly — but only for the
+          categories you enable here. Disabled categories fall back to an ad-hoc walk
+          or escalation.
+        </p>
+      </div>
+
+      <div className="space-y-2">
+        {data.available.map((cat) => {
+          const checked = data.enabled.includes(cat)
+          return (
+            <label
+              key={cat}
+              className="flex items-center gap-3 rounded-md border border-default bg-card px-4 py-3 cursor-pointer hover:bg-elevated transition-colors"
+            >
+              <input
+                type="checkbox"
+                checked={checked}
+                disabled={saving === cat}
+                onChange={() => toggle(cat)}
+                className="h-4 w-4 accent-accent"
+              />
+              <span className="text-sm text-primary">{prettify(cat)}</span>
+            </label>
+          )
+        })}
+      </div>
+
+      <div>
+        <h2 className="font-heading text-sm font-semibold text-heading mb-2">
+          Always excluded (safety)
+        </h2>
+        <p className="text-xs text-muted-foreground mb-2">
+          These action classes are never built automatically and cannot be enabled.
+        </p>
+        <ul className="list-disc pl-5 text-xs text-muted-foreground space-y-1">
+          {data.hard_floor.map((h) => (
+            <li key={h}>{prettify(h)}</li>
+          ))}
+        </ul>
+      </div>
+    </div>
+  )
+}
diff --git a/frontend/src/router.tsx b/frontend/src/router.tsx
index 78c6336d..61f07f00 100644
--- a/frontend/src/router.tsx
+++ b/frontend/src/router.tsx
@@ -114,6 +114,7 @@ const IntegrationsPage = lazyWithRetry(() => import('@/pages/account/Integration
 const BrandingSettingsPage = lazyWithRetry(() => import('@/pages/account/BrandingSettingsPage'))
 const BillingPage = lazyWithRetry(() => import('@/pages/account/BillingPage'))
 const SelectPlanPage = lazyWithRetry(() => import('@/pages/account/SelectPlanPage'))
+const L1CategoriesPage = lazyWithRetry(() => import('@/pages/account/L1CategoriesPage'))
 
 /** Wraps a lazy-loaded page with Suspense + ErrorBoundary */
 function page(Component: React.LazyExoticComponent<React.ComponentType>) {
@@ -363,6 +364,14 @@ export const router = sentryCreateBrowserRouter([
               </ProtectedRoute>
             ),
           },
+          {
+            path: 'l1-categories',
+            element: (
+              <ProtectedRoute requiredRole="owner">
+                {page(L1CategoriesPage)}
+              </ProtectedRoute>
+            ),
+          },
           {
             path: 'chat-retention',
             element: (