diff --git a/packages/ui/src/components/instance/shell/SessionSidebar.tsx b/packages/ui/src/components/instance/shell/SessionSidebar.tsx
index affce5dd..6f3fd70a 100644
--- a/packages/ui/src/components/instance/shell/SessionSidebar.tsx
+++ b/packages/ui/src/components/instance/shell/SessionSidebar.tsx
@@ -4,7 +4,7 @@ import type { Session } from "../../../types/session"
 import type { KeyboardShortcut } from "../../../lib/keyboard-registry"
 import type { DrawerViewState } from "./types"
 
-import { Search } from "lucide-solid"
+import { PlusSquare, Search } from "lucide-solid"
 import IconButton from "@suid/material/IconButton"
 import MenuOpenIcon from "@suid/icons-material/MenuOpen"
 import PushPinIcon from "@suid/icons-material/PushPin"
@@ -56,6 +56,20 @@ const SessionSidebar: Component<SessionSidebarProps> = (props) => (
           {props.t("instanceShell.leftPanel.sessionsTitle")}
         </span>
         <div class="flex items-center gap-2 text-primary">
+          <IconButton
+            size="small"
+            color="inherit"
+            aria-label={props.t("sessionList.actions.newSession.ariaLabel")}
+            title={props.t("sessionList.actions.newSession.title")}
+            onClick={() => {
+              const result = props.onNewSession()
+              if (result instanceof Promise) {
+                void result.catch((error) => log.error("Failed to create session:", error))
+              }
+            }}
+          >
+            <PlusSquare class="w-5 h-5" />
+          </IconButton>
           <IconButton
             size="small"
             color="inherit"
@@ -71,7 +85,7 @@ const SessionSidebar: Component<SessionSidebarProps> = (props) => (
               },
             }}
           >
-            <Search class={props.showSearch() ? "w-4 h-4" : "w-4 h-4 opacity-70"} />
+            <Search class="w-5 h-5" />
           </IconButton>
           <IconButton
             size="small"
diff --git a/packages/ui/src/lib/i18n/messages/en/session.ts b/packages/ui/src/lib/i18n/messages/en/session.ts
index 0cba5509..699c50d6 100644
--- a/packages/ui/src/lib/i18n/messages/en/session.ts
+++ b/packages/ui/src/lib/i18n/messages/en/session.ts
@@ -21,6 +21,8 @@ export const sessionMessages = {
   "sessionList.expand.expandAriaLabel": "Expand session",
   "sessionList.expand.collapseTitle": "Collapse",
   "sessionList.expand.expandTitle": "Expand",
+  "sessionList.actions.newSession.ariaLabel": "New session",
+  "sessionList.actions.newSession.title": "New session",
   "sessionList.actions.copyId.ariaLabel": "Copy session ID",
   "sessionList.actions.copyId.title": "Copy session ID",
   "sessionList.actions.rename.ariaLabel": "Rename session",
diff --git a/packages/ui/src/lib/i18n/messages/es/session.ts b/packages/ui/src/lib/i18n/messages/es/session.ts
index ecdac0d7..8c9dc7b4 100644
--- a/packages/ui/src/lib/i18n/messages/es/session.ts
+++ b/packages/ui/src/lib/i18n/messages/es/session.ts
@@ -21,6 +21,8 @@ export const sessionMessages = {
   "sessionList.expand.expandAriaLabel": "Expandir sesión",
   "sessionList.expand.collapseTitle": "Colapsar",
   "sessionList.expand.expandTitle": "Expandir",
+  "sessionList.actions.newSession.ariaLabel": "Nueva sesión",
+  "sessionList.actions.newSession.title": "Nueva sesión",
   "sessionList.actions.copyId.ariaLabel": "Copiar ID de sesión",
   "sessionList.actions.copyId.title": "Copiar ID de sesión",
   "sessionList.actions.rename.ariaLabel": "Renombrar sesión",
diff --git a/packages/ui/src/lib/i18n/messages/fr/session.ts b/packages/ui/src/lib/i18n/messages/fr/session.ts
index 7bee6007..64baf1c8 100644
--- a/packages/ui/src/lib/i18n/messages/fr/session.ts
+++ b/packages/ui/src/lib/i18n/messages/fr/session.ts
@@ -21,6 +21,8 @@ export const sessionMessages = {
   "sessionList.expand.expandAriaLabel": "Développer la session",
   "sessionList.expand.collapseTitle": "Réduire",
   "sessionList.expand.expandTitle": "Développer",
+  "sessionList.actions.newSession.ariaLabel": "Nouvelle session",
+  "sessionList.actions.newSession.title": "Nouvelle session",
   "sessionList.actions.copyId.ariaLabel": "Copier l'ID de session",
   "sessionList.actions.copyId.title": "Copier l'ID de session",
   "sessionList.actions.rename.ariaLabel": "Renommer la session",
diff --git a/packages/ui/src/lib/i18n/messages/ja/session.ts b/packages/ui/src/lib/i18n/messages/ja/session.ts
index ca5e2d09..ae7e60a2 100644
--- a/packages/ui/src/lib/i18n/messages/ja/session.ts
+++ b/packages/ui/src/lib/i18n/messages/ja/session.ts
@@ -21,6 +21,8 @@ export const sessionMessages = {
   "sessionList.expand.expandAriaLabel": "セッションを展開",
   "sessionList.expand.collapseTitle": "折りたたむ",
   "sessionList.expand.expandTitle": "展開",
+  "sessionList.actions.newSession.ariaLabel": "新しいセッション",
+  "sessionList.actions.newSession.title": "新しいセッション",
   "sessionList.actions.copyId.ariaLabel": "セッション ID をコピー",
   "sessionList.actions.copyId.title": "セッション ID をコピー",
   "sessionList.actions.rename.ariaLabel": "セッション名を変更",
diff --git a/packages/ui/src/lib/i18n/messages/ru/session.ts b/packages/ui/src/lib/i18n/messages/ru/session.ts
index f15194e2..8d348183 100644
--- a/packages/ui/src/lib/i18n/messages/ru/session.ts
+++ b/packages/ui/src/lib/i18n/messages/ru/session.ts
@@ -21,6 +21,8 @@ export const sessionMessages = {
   "sessionList.expand.expandAriaLabel": "Развернуть сессию",
   "sessionList.expand.collapseTitle": "Свернуть",
   "sessionList.expand.expandTitle": "Развернуть",
+  "sessionList.actions.newSession.ariaLabel": "Новая сессия",
+  "sessionList.actions.newSession.title": "Новая сессия",
   "sessionList.actions.copyId.ariaLabel": "Скопировать ID сессии",
   "sessionList.actions.copyId.title": "Скопировать ID сессии",
   "sessionList.actions.rename.ariaLabel": "Переименовать сессию",
diff --git a/packages/ui/src/lib/i18n/messages/zh-Hans/session.ts b/packages/ui/src/lib/i18n/messages/zh-Hans/session.ts
index 3dfc79a8..c9ebb0d3 100644
--- a/packages/ui/src/lib/i18n/messages/zh-Hans/session.ts
+++ b/packages/ui/src/lib/i18n/messages/zh-Hans/session.ts
@@ -21,6 +21,8 @@ export const sessionMessages = {
   "sessionList.expand.expandAriaLabel": "展开会话",
   "sessionList.expand.collapseTitle": "折叠",
   "sessionList.expand.expandTitle": "展开",
+  "sessionList.actions.newSession.ariaLabel": "新建会话",
+  "sessionList.actions.newSession.title": "新建会话",
   "sessionList.actions.copyId.ariaLabel": "复制会话 ID",
   "sessionList.actions.copyId.title": "复制会话 ID",
   "sessionList.actions.rename.ariaLabel": "重命名会话",