diff --git a/packages/extension/src/agent/constants.ts b/packages/extension/src/agent/constants.ts
index bba9ca8..0b90164 100644
--- a/packages/extension/src/agent/constants.ts
+++ b/packages/extension/src/agent/constants.ts
@@ -10,3 +10,21 @@ export const DEMO_CONFIG: LLMConfig = {
 	baseURL: DEMO_BASE_URL,
 	model: DEMO_MODEL,
 }
+
+/** Legacy testing endpoints that should be auto-migrated to DEMO_BASE_URL */
+export const LEGACY_TESTING_ENDPOINTS = [
+	'https://hwcxiuzfylggtcktqgij.supabase.co/functions/v1/llm-testing-proxy',
+]
+
+export function isTestingEndpoint(url: string): boolean {
+	const normalized = url.replace(/\/+$/, '')
+	return normalized === DEMO_BASE_URL || LEGACY_TESTING_ENDPOINTS.some((ep) => normalized === ep)
+}
+
+export function migrateLegacyEndpoint(config: LLMConfig): LLMConfig {
+	const normalized = config.baseURL.replace(/\/+$/, '')
+	if (LEGACY_TESTING_ENDPOINTS.some((ep) => normalized === ep)) {
+		return { ...DEMO_CONFIG }
+	}
+	return config
+}
diff --git a/packages/extension/src/agent/useAgent.ts b/packages/extension/src/agent/useAgent.ts
index 6b28c49..db53294 100644
--- a/packages/extension/src/agent/useAgent.ts
+++ b/packages/extension/src/agent/useAgent.ts
@@ -11,7 +11,7 @@ import type { LLMConfig } from '@page-agent/llms'
 import { useCallback, useEffect, useRef, useState } from 'react'
 
 import { MultiPageAgent } from './MultiPageAgent'
-import { DEMO_CONFIG } from './constants'
+import { DEMO_CONFIG, migrateLegacyEndpoint } from './constants'
 
 /** Language preference: undefined means follow system */
 export type LanguagePreference = SupportedLanguage | undefined
@@ -41,13 +41,19 @@ export function useAgent(): UseAgentResult {
 
 	useEffect(() => {
 		chrome.storage.local.get(['llmConfig', 'language']).then((result) => {
-			const llmConfig = (result.llmConfig as LLMConfig) ?? DEMO_CONFIG
+			let llmConfig = (result.llmConfig as LLMConfig) ?? DEMO_CONFIG
 			const language = (result.language as SupportedLanguage) || undefined
-			const full = { ...llmConfig, language }
-			if (!result.llmConfig) {
+
+			// Auto-migrate legacy testing endpoints
+			const migrated = migrateLegacyEndpoint(llmConfig)
+			if (migrated !== llmConfig) {
+				llmConfig = migrated
+				chrome.storage.local.set({ llmConfig: migrated })
+			} else if (!result.llmConfig) {
 				chrome.storage.local.set({ llmConfig: DEMO_CONFIG })
 			}
-			setConfig(full)
+
+			setConfig({ ...llmConfig, language })
 		})
 	}, [])
 
diff --git a/packages/extension/src/entrypoints/sidepanel/components/ConfigPanel.tsx b/packages/extension/src/entrypoints/sidepanel/components/ConfigPanel.tsx
index 977071e..efcaf88 100644
--- a/packages/extension/src/entrypoints/sidepanel/components/ConfigPanel.tsx
+++ b/packages/extension/src/entrypoints/sidepanel/components/ConfigPanel.tsx
@@ -2,7 +2,7 @@ import { Copy, CornerUpLeft, Eye, EyeOff, HatGlasses, Home, Loader2, Scale } fro
 import { useEffect, useState } from 'react'
 import { siGithub } from 'simple-icons'
 
-import { DEMO_API_KEY, DEMO_BASE_URL, DEMO_MODEL } from '@/agent/constants'
+import { DEMO_API_KEY, DEMO_BASE_URL, DEMO_MODEL, isTestingEndpoint } from '@/agent/constants'
 import type { ExtConfig, LanguagePreference } from '@/agent/useAgent'
 import { Button } from '@/components/ui/button'
 import { Input } from '@/components/ui/input'
@@ -87,6 +87,23 @@ export function ConfigPanel({ config, onSave, onClose }: ConfigPanelProps) {
 				</Button>
 			</div>
 
+			{/* Testing API notice */}
+			{isTestingEndpoint(baseURL) && (
+				<div className="p-2.5 rounded-md border border-amber-500/30 bg-amber-500/5 text-[10px] text-muted-foreground leading-relaxed">
+					<Scale className="size-3 inline-block mr-1 -mt-0.5 text-amber-600" />
+					You are using the free testing API. By using this service you agree to the{' '}
+					<a
+						href="https://github.com/alibaba/page-agent/blob/main/docs/terms-and-privacy.md"
+						target="_blank"
+						rel="noopener noreferrer"
+						className="underline hover:text-foreground"
+					>
+						Terms of Use & Privacy Policy
+					</a>
+					. No sensitive data. No guaranteed availability.
+				</div>
+			)}
+
 			{/* User Auth Token Section */}
 			<div className="flex flex-col gap-1.5 p-3 bg-muted/50 rounded-md border">
 				<label className="text-xs font-medium text-muted-foreground">User Auth Token</label>