diff --git a/frontend/src/App.test.tsx b/frontend/src/App.test.tsx
index 1ed7b037..22a1aea8 100644
--- a/frontend/src/App.test.tsx
+++ b/frontend/src/App.test.tsx
@@ -19,6 +19,7 @@ vi.mock("./api/client", () => {
 		setModelPreference: vi.fn(),
 		cancelChat: vi.fn(),
 		setAnthropicApiKey: vi.fn(),
+		getOAuthStatus: vi.fn(),
 	};
 	class ChatWebSocket {
 		connect() {}
@@ -65,6 +66,7 @@ describe("App", () => {
 		mockedApi.getAnthropicApiKeyExists.mockResolvedValue(false);
 		mockedApi.getAnthropicModels.mockResolvedValue([]);
 		mockedApi.getModelPreference.mockResolvedValue(null);
+		mockedApi.getOAuthStatus.mockResolvedValue({ authenticated: false, expired: false, expires_at: 0, has_refresh_token: false });
 	});
 
 	async function renderApp() {
diff --git a/frontend/src/App.tsx b/frontend/src/App.tsx
index 316029a8..49533e9a 100644
--- a/frontend/src/App.tsx
+++ b/frontend/src/App.tsx
@@ -1,4 +1,5 @@
 import * as React from "react";
+import type { OAuthStatus } from "./api/client";
 import { api } from "./api/client";
 import { Chat } from "./components/Chat";
 import { SelectionScreen } from "./components/selection/SelectionScreen";
@@ -14,6 +15,27 @@ function App() {
 	const [isOpening, setIsOpening] = React.useState(false);
 	const [knownProjects, setKnownProjects] = React.useState<string[]>([]);
 	const [homeDir, setHomeDir] = React.useState<string | null>(null);
+	const [oauthStatus, setOauthStatus] = React.useState<OAuthStatus | null>(
+		null,
+	);
+
+	React.useEffect(() => {
+		let active = true;
+		function fetchOAuthStatus() {
+			api
+				.getOAuthStatus()
+				.then((s) => {
+					if (active) setOauthStatus(s);
+				})
+				.catch(() => {});
+		}
+		fetchOAuthStatus();
+		const intervalId = window.setInterval(fetchOAuthStatus, 5000);
+		return () => {
+			active = false;
+			window.clearInterval(intervalId);
+		};
+	}, []);
 
 	React.useEffect(() => {
 		api
@@ -182,10 +204,15 @@ function App() {
 					onCloseSuggestions={closeSuggestions}
 					completionError={completionError}
 					currentPartial={currentPartial}
+					oauthStatus={oauthStatus}
 				/>
 			) : (
 				<div className="workspace" style={{ height: "100%" }}>
-					<Chat projectPath={projectPath} onCloseProject={closeProject} />
+					<Chat
+						projectPath={projectPath}
+						onCloseProject={closeProject}
+						oauthStatus={oauthStatus}
+					/>
 				</div>
 			)}
 
diff --git a/frontend/src/api/client.ts b/frontend/src/api/client.ts
index 335b8016..3f690345 100644
--- a/frontend/src/api/client.ts
+++ b/frontend/src/api/client.ts
@@ -205,6 +205,13 @@ export interface CommandOutput {
 	exit_code: number;
 }
 
+export interface OAuthStatus {
+	authenticated: boolean;
+	expired: boolean;
+	expires_at: number;
+	has_refresh_token: boolean;
+}
+
 declare const __STORKIT_PORT__: string;
 
 const DEFAULT_API_BASE = "/api";
@@ -402,6 +409,10 @@ export const api = {
 	deleteStory(storyId: string) {
 		return callMcpTool("delete_story", { story_id: storyId });
 	},
+	/** Fetch OAuth status from the server. */
+	getOAuthStatus() {
+		return requestJson<OAuthStatus>("/oauth/status", {}, "");
+	},
 	/** Execute a bot slash command without LLM invocation. Returns markdown response text. */
 	botCommand(command: string, args: string, baseUrl?: string) {
 		return requestJson<{ response: string }>(
diff --git a/frontend/src/components/Chat.tsx b/frontend/src/components/Chat.tsx
index 133f1660..1ca6a423 100644
--- a/frontend/src/components/Chat.tsx
+++ b/frontend/src/components/Chat.tsx
@@ -6,6 +6,7 @@ import type { AgentConfigInfo } from "../api/agents";
 import { agentsApi } from "../api/agents";
 import type {
 	AnthropicModelInfo,
+	OAuthStatus,
 	PipelineState,
 	WizardStateData,
 } from "../api/client";
@@ -164,9 +165,10 @@ const getContextWindowSize = (
 interface ChatProps {
 	projectPath: string;
 	onCloseProject: () => void;
+	oauthStatus?: OAuthStatus | null;
 }
 
-export function Chat({ projectPath, onCloseProject }: ChatProps) {
+export function Chat({ projectPath, onCloseProject, oauthStatus = null }: ChatProps) {
 	const { messages, setMessages, clearMessages } = useChatHistory(projectPath);
 	const [loading, setLoading] = useState(false);
 	const [model, setModel] = useState("claude-code-pty");
@@ -940,6 +942,7 @@ export function Chat({ projectPath, onCloseProject }: ChatProps) {
 				enableTools={enableTools}
 				onToggleTools={setEnableTools}
 				wsConnected={wsConnected}
+				oauthStatus={oauthStatus}
 			/>
 
 			{/* Two-column content area */}
diff --git a/frontend/src/components/ChatHeader.tsx b/frontend/src/components/ChatHeader.tsx
index 5bed248c..83b5b25c 100644
--- a/frontend/src/components/ChatHeader.tsx
+++ b/frontend/src/components/ChatHeader.tsx
@@ -1,4 +1,5 @@
 import * as React from "react";
+import type { OAuthStatus } from "../api/client";
 import { api } from "../api/client";
 
 const { useState, useEffect } = React;
@@ -32,6 +33,7 @@ interface ChatHeaderProps {
 	enableTools: boolean;
 	onToggleTools: (enabled: boolean) => void;
 	wsConnected: boolean;
+	oauthStatus?: OAuthStatus | null;
 }
 
 const getContextEmoji = (percentage: number): string => {
@@ -55,6 +57,7 @@ export function ChatHeader({
 	enableTools,
 	onToggleTools,
 	wsConnected,
+	oauthStatus = null,
 }: ChatHeaderProps) {
 	const hasModelOptions = availableModels.length > 0 || claudeModels.length > 0;
 	const [showConfirm, setShowConfirm] = useState(false);
@@ -340,6 +343,59 @@ export function ChatHeader({
 				</div>
 
 				<div style={{ display: "flex", alignItems: "center", gap: "16px" }}>
+					{oauthStatus !== null &&
+						(!oauthStatus.authenticated || oauthStatus.expired) && (
+							<button
+								type="button"
+								title="Authenticate with Claude via OAuth"
+								onClick={() => {
+									window.open("/oauth/authorize", "_blank", "noopener,noreferrer");
+								}}
+								style={{
+									padding: "6px 12px",
+									borderRadius: "99px",
+									border: "none",
+									fontSize: "0.85em",
+									backgroundColor: "#1a3a5c",
+									color: "#7eb8f7",
+									cursor: "pointer",
+									outline: "none",
+									transition: "all 0.2s",
+									whiteSpace: "nowrap",
+								}}
+								onMouseOver={(e) => {
+									e.currentTarget.style.backgroundColor = "#234d7a";
+									e.currentTarget.style.color = "#a8d4ff";
+								}}
+								onMouseOut={(e) => {
+									e.currentTarget.style.backgroundColor = "#1a3a5c";
+									e.currentTarget.style.color = "#7eb8f7";
+								}}
+								onFocus={(e) => {
+									e.currentTarget.style.backgroundColor = "#234d7a";
+									e.currentTarget.style.color = "#a8d4ff";
+								}}
+								onBlur={(e) => {
+									e.currentTarget.style.backgroundColor = "#1a3a5c";
+									e.currentTarget.style.color = "#7eb8f7";
+								}}
+							>
+								{oauthStatus.expired ? "Re-authenticate" : "Login with Claude"}
+							</button>
+						)}
+					{oauthStatus?.authenticated && !oauthStatus.expired && (
+						<span
+							title="Authenticated with Claude via OAuth"
+							style={{
+								fontSize: "0.8em",
+								color: "#4caf50",
+								whiteSpace: "nowrap",
+							}}
+						>
+							✓ Claude
+						</span>
+					)}
+
 					<div
 						style={{
 							fontSize: "0.75em",
diff --git a/frontend/src/components/selection/SelectionScreen.tsx b/frontend/src/components/selection/SelectionScreen.tsx
index ecc6fdd3..9b3a637e 100644
--- a/frontend/src/components/selection/SelectionScreen.tsx
+++ b/frontend/src/components/selection/SelectionScreen.tsx
@@ -1,4 +1,5 @@
 import type { KeyboardEvent } from "react";
+import type { OAuthStatus } from "../../api/client";
 import { ProjectPathInput } from "./ProjectPathInput.tsx";
 import { RecentProjectsList } from "./RecentProjectsList.tsx";
 
@@ -24,6 +25,7 @@ export interface SelectionScreenProps {
 	onCloseSuggestions: () => void;
 	completionError: string | null;
 	currentPartial: string;
+	oauthStatus?: OAuthStatus | null;
 }
 
 export function SelectionScreen({
@@ -43,6 +45,7 @@ export function SelectionScreen({
 	onCloseSuggestions,
 	completionError,
 	currentPartial,
+	oauthStatus = null,
 }: SelectionScreenProps) {
 	const resolvedHomeDir = homeDir
 		? homeDir.endsWith("/")
@@ -57,6 +60,37 @@ export function SelectionScreen({
 			<h1>Storkit</h1>
 			<p>Paste or complete a project path to start.</p>
 
+			{oauthStatus !== null && (
+				<div style={{ marginBottom: "1rem" }}>
+					{!oauthStatus.authenticated || oauthStatus.expired ? (
+						<button
+							type="button"
+							onClick={() => {
+								window.open("/oauth/authorize", "_blank", "noopener,noreferrer");
+							}}
+							style={{
+								padding: "8px 16px",
+								borderRadius: "6px",
+								border: "1px solid #1a3a5c",
+								backgroundColor: "#1a3a5c",
+								color: "#7eb8f7",
+								cursor: "pointer",
+								fontSize: "0.9em",
+							}}
+						>
+							{oauthStatus.expired ? "Re-authenticate with Claude" : "Login with Claude"}
+						</button>
+					) : (
+						<span
+							title="Authenticated with Claude via OAuth"
+							style={{ color: "#4caf50", fontSize: "0.9em" }}
+						>
+							✓ Authenticated with Claude
+						</span>
+					)}
+				</div>
+			)}
+
 			{knownProjects.length > 0 && (
 				<RecentProjectsList
 					projects={knownProjects}
diff --git a/frontend/vite.config.ts b/frontend/vite.config.ts
index 2fa69d2a..b54a7532 100644
--- a/frontend/vite.config.ts
+++ b/frontend/vite.config.ts
@@ -30,6 +30,20 @@ export default defineConfig(() => {
 						proxy.on("error", (_err) => {});
 					},
 				},
+				"/oauth": {
+					target: `http://127.0.0.1:${String(backendPort)}`,
+					timeout: 120000,
+					configure: (proxy) => {
+						proxy.on("error", (_err) => {});
+					},
+				},
+				"/callback": {
+					target: `http://127.0.0.1:${String(backendPort)}`,
+					timeout: 120000,
+					configure: (proxy) => {
+						proxy.on("error", (_err) => {});
+					},
+				},
 			},
 			watch: {
 				ignored: [