diff --git a/packages/app/src/context/global-sync/event-reducer.ts b/packages/app/src/context/global-sync/event-reducer.ts
index 4af636553526..06b767b7d5b9 100644
--- a/packages/app/src/context/global-sync/event-reducer.ts
+++ b/packages/app/src/context/global-sync/event-reducer.ts
@@ -162,7 +162,8 @@ export function applyDirectoryEvent(input: {
     }
     case "session.diff": {
       const props = event.properties as { sessionID: string; diff: FileDiff[] }
-      input.setStore("session_diff", props.sessionID, reconcile(props.diff, { key: "file" }))
+      const diff = Array.isArray(props.diff) ? props.diff : []
+      input.setStore("session_diff", props.sessionID, reconcile(diff, { key: "file" }))
       break
     }
     case "todo.updated": {
diff --git a/packages/app/src/pages/session.tsx b/packages/app/src/pages/session.tsx
index 8c32a7237f58..d191560c1524 100644
--- a/packages/app/src/pages/session.tsx
+++ b/packages/app/src/pages/session.tsx
@@ -426,7 +426,11 @@ export default function Page() {
   }
 
   const info = createMemo(() => (params.id ? sync.session.get(params.id) : undefined))
-  const diffs = createMemo(() => (params.id ? (sync.data.session_diff[params.id] ?? []) : []))
+  const diffs = createMemo(() => {
+    if (!params.id) return []
+    const d = sync.data.session_diff[params.id]
+    return Array.isArray(d) ? d : []
+  })
   const sessionCount = createMemo(() => Math.max(info()?.summary?.files ?? 0, diffs().length))
   const hasSessionReview = createMemo(() => sessionCount() > 0)
   const canReview = createMemo(() => !!params.id)
@@ -636,7 +640,10 @@ export default function Page() {
     return open
   }, desktopReviewOpen())
 
-  const turnDiffs = createMemo(() => lastUserMessage()?.summary?.diffs ?? [])
+  const turnDiffs = createMemo(() => {
+    const d = lastUserMessage()?.summary?.diffs
+    return Array.isArray(d) ? d : []
+  })
   const changesOptions = createMemo<ChangeMode[]>(() => {
     const list: ChangeMode[] = []
     if (sync.project?.vcs === "git") list.push("git")
diff --git a/packages/ui/src/components/session-review.tsx b/packages/ui/src/components/session-review.tsx
index 2274e93a34b5..662abe5e3a6b 100644
--- a/packages/ui/src/components/session-review.tsx
+++ b/packages/ui/src/components/session-review.tsx
@@ -150,7 +150,8 @@ export const SessionReview = (props: SessionReviewProps) => {
   const opened = () => store.opened
 
   const open = () => props.open ?? store.open
-  const files = createMemo(() => props.diffs.map((diff) => diff.file))
+  const safe = () => (Array.isArray(props.diffs) ? props.diffs : [])
+  const files = createMemo(() => safe().map((diff) => diff.file))
   const diffStyle = () => props.diffStyle ?? (props.split ? "split" : "unified")
   const hasDiffs = () => files().length > 0
 
@@ -281,7 +282,7 @@ export const SessionReview = (props: SessionReviewProps) => {
           <Show when={hasDiffs()} fallback={props.empty}>
             <div class="pb-6">
               <Accordion multiple value={open()} onChange={handleChange}>
-                <For each={props.diffs}>
+                <For each={safe()}>
                   {(diff) => {
                     let wrapper: HTMLDivElement | undefined
                     const file = diff.file