diff --git a/src/api.ts b/src/api.ts
index 30af7b7..5fe8429 100644
--- a/src/api.ts
+++ b/src/api.ts
@@ -28,6 +28,8 @@ export const api = {
   listTasks: (includeArchived?: boolean) => auth.fetch(`${BASE}/api/conversations${includeArchived ? '?archived=1' : ''}`).then(r => json<Conversation[]>(r)),
   setConversationFlags: (id: string, flags: { pinned?: boolean; archived?: boolean; allowCrossRead?: boolean; crossPrivate?: boolean }) => auth.fetch(`${BASE}/api/conversations/${id}`, { method: 'PATCH', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify(flags) }).then(r => { if (!r.ok) throw new Error(`${r.status}: ${r.statusText}`) }),
   setPermissionMode: (id: string, permissionMode: string) => auth.fetch(`${BASE}/api/conversations/${id}`, { method: 'PATCH', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ permissionMode }) }).then(r => { if (!r.ok) throw new Error(`${r.status}: ${r.statusText}`) }),
+  checkpoints: (id: string, messageId: string) => auth.fetch(`${BASE}/api/conversations/${id}/checkpoints?messageId=${encodeURIComponent(messageId)}`).then(r => json<{ restored?: string[]; skipped?: string[] }>(r)),
+  rewindFiles: (id: string, messageId: string) => auth.fetch(`${BASE}/api/conversations/${id}/rewind`, { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ messageId }) }).then(r => json<{ restored?: string[]; skipped?: string[] }>(r)),
   me: () => auth.fetch(`${BASE}/api/me`).then(r => json<{ owner: string; name: string; auth: boolean; isAdmin?: boolean; mustChangePassword?: boolean }>(r)),
   // ---- 认证与会话（管理员发放制，R2）----
   login: (owner: string, password: string) => auth.fetch(`${BASE}/api/auth/login`, { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ owner, password }) }).then(async r => {
diff --git a/src/components/Conversation.tsx b/src/components/Conversation.tsx
index 3103106..7e33872 100644
--- a/src/components/Conversation.tsx
+++ b/src/components/Conversation.tsx
@@ -540,6 +540,7 @@ export function Conversation() {
                   <span className="role-mark"><Avatar name={myName} size="sm" /></span>你
                 </div>
                 <div className="bubble">{m.parts.filter(p => p.type === 'text').map(p => p.text).join('\n')}</div>
+                {currentConvId && <RewindControl convId={currentConvId} messageId={m.id} />}
                 {anchored.map(c => (
                   <InlineConfirmCard key={c.id} card={c} callbacks={{
                     onAction: (card, actionId) => store.cardAction(card, actionId),
@@ -616,3 +617,63 @@ export function Conversation() {
     </div>
   )
 }
+
+function RewindControl({ convId, messageId }: { convId: string; messageId: string }) {
+  const [open, setOpen] = useState(false)
+  const [files, setFiles] = useState<{ restored: string[]; skipped: string[] } | null>(null)
+  const [busy, setBusy] = useState(false)
+  const [err, setErr] = useState('')
+  async function preview() {
+    setErr('')
+    setOpen(true)
+    setFiles(null)
+    try {
+      const plan = await api.checkpoints(convId, messageId)
+      setFiles({ restored: plan.restored ?? [], skipped: plan.skipped ?? [] })
+    } catch (e) {
+      setErr(e instanceof Error ? e.message : String(e))
+    }
+  }
+  async function confirm() {
+    setBusy(true)
+    setErr('')
+    try {
+      await api.rewindFiles(convId, messageId)
+      setOpen(false)
+      await store.openTask(convId)
+    } catch (e) {
+      setErr(e instanceof Error ? e.message : String(e))
+    } finally {
+      setBusy(false)
+    }
+  }
+  const canRewind = !!files && files.restored.length > 0
+  return (
+    <div className="rewind-row">
+      <button type="button" className="btn ghost" onClick={preview}>回滚文件</button>
+      {open && (
+        <div className="rewind-panel" role="dialog" aria-label="回滚文件">
+          {!files && !err && <div>正在列出文件…</div>}
+          {files && files.restored.length === 0 && files.skipped.length === 0 && <div>没有需要回滚的文件。</div>}
+          {files && files.restored.length > 0 && (
+            <>
+              <div>将恢复这些文件：</div>
+              <ul>{files.restored.map(p => <li key={p}>{p}</li>)}</ul>
+            </>
+          )}
+          {files && files.skipped.length > 0 && (
+            <>
+              <div>这些文件在追踪之外被改过，会跳过：</div>
+              <ul>{files.skipped.map(p => <li key={`skip-${p}`}>{p}</li>)}</ul>
+            </>
+          )}
+          {err && <div className="rewind-error">{err}</div>}
+          <div className="rewind-actions">
+            <button type="button" className="btn" disabled={busy || !canRewind} onClick={confirm}>确认回滚</button>
+            <button type="button" className="btn ghost" onClick={() => setOpen(false)}>取消</button>
+          </div>
+        </div>
+      )}
+    </div>
+  )
+}
diff --git a/src/contracts.ts b/src/contracts.ts
index 64044d6..43046eb 100644
--- a/src/contracts.ts
+++ b/src/contracts.ts
@@ -55,6 +55,7 @@ export type RunPhase = 'thinking' | 'acting' | 'responding' | 'finalizing' | 'do
 export interface Usage {
   promptTokens: number; completionTokens: number; totalTokens: number;
   durationMs: number; toolCalls: number;
+  model?: string;
 }
 
 export interface Run {
diff --git a/src/styles.css b/src/styles.css
index 483a035..746291a 100644
--- a/src/styles.css
+++ b/src/styles.css
@@ -553,3 +553,12 @@ button { font-family: inherit; font-size: inherit; color: inherit; }
   margin-left: 6px; min-width: 16px; padding: 0 5px; border-radius: var(--radius-full);
   background: var(--err); color: var(--text-on-accent); font-size: var(--fs-ui-xs);
 }
+.rewind-row { margin-top: 8px; }
+.rewind-panel {
+  margin-top: 8px; padding: 8px 10px;
+  background: var(--bg-raised); border: 1px solid var(--border); border-radius: var(--radius-sm);
+  font-size: var(--fs-ui-sm);
+}
+.rewind-panel ul { margin: 6px 0; padding-left: 1.2em; }
+.rewind-actions { display: flex; gap: 8px; }
+.rewind-error { color: var(--err); font-size: var(--fs-ui-sm); }