diff --git a/src/renderer/src/components/settings/AntigravityChatSignInRow.test.tsx b/src/renderer/src/components/settings/AntigravityChatSignInRow.test.tsx
index 88980f2aa3c6..09d870d5490f 100644
--- a/src/renderer/src/components/settings/AntigravityChatSignInRow.test.tsx
+++ b/src/renderer/src/components/settings/AntigravityChatSignInRow.test.tsx
@@ -163,28 +163,30 @@ it('sends the address pasted from a browser on another computer to the host', as
 it("names the account and why it's needed before the host knows its sign-in", async () => {
   const owner = { kind: 'environment', environmentId: 'provider-unanswered' } as const
   render(
-    <AntigravityProviderSignInArea
-      owner={owner}
-      label="this computer"
-      install={{
-        kind: 'active',
-        subject: { target: owner, runtimeId: null, agent: 'antigravity' },
-        removable: true,
-        snapshot: {
-          kind: 'known',
-          state: {
-            agent: 'antigravity',
-            revision: 1,
-            available: true,
-            version: '1.0.0',
-            installedVersion: '1.0.0',
-            installedCurrent: true,
-            source: 'managed',
-            operation: null
+    <TooltipProvider>
+      <AntigravityProviderSignInArea
+        owner={owner}
+        label="this computer"
+        install={{
+          kind: 'active',
+          subject: { target: owner, runtimeId: null, agent: 'antigravity' },
+          removable: true,
+          snapshot: {
+            kind: 'known',
+            state: {
+              agent: 'antigravity',
+              revision: 1,
+              available: true,
+              version: '1.0.0',
+              installedVersion: '1.0.0',
+              installedCurrent: true,
+              source: 'managed',
+              operation: null
+            }
           }
-        }
-      }}
-    />
+        }}
+      />
+    </TooltipProvider>
   )
   await act(async () => undefined)
   expect(screen.getByText('Account')).toBeTruthy()
diff --git a/src/renderer/src/components/settings/AntigravityChatSignInRow.tsx b/src/renderer/src/components/settings/AntigravityChatSignInRow.tsx
index e81a65b76043..8b74bae209e4 100644
--- a/src/renderer/src/components/settings/AntigravityChatSignInRow.tsx
+++ b/src/renderer/src/components/settings/AntigravityChatSignInRow.tsx
@@ -1,5 +1,5 @@
 import { useEffect, useId, useState, useSyncExternalStore } from 'react'
-import { Check, Copy } from 'lucide-react'
+import { Check, Copy, Info } from 'lucide-react'
 import { translate } from '@/i18n/i18n'
 import { useClipboardTextCopyFeedback } from '@/hooks/use-clipboard-text-copy-feedback'
 import {
@@ -202,6 +202,26 @@ export function PastedAddressForm(props: {
   )
 }
 
+/** Beside the sign-in button: users expect their agy CLI login to carry over to chats. */
+export function AntigravityChatSignInInfo(): React.JSX.Element {
+  const label = translate('accounts.antigravity.chatSignInInfoLabel', 'About Antigravity sign-in')
+  return (
+    <Tooltip>
+      <TooltipTrigger asChild>
+        <Button size="icon-xs" variant="ghost" aria-label={label}>
+          <Info className="text-muted-foreground" />
+        </Button>
+      </TooltipTrigger>
+      <TooltipContent side="top" sideOffset={4} className="max-w-xs">
+        {translate(
+          'accounts.antigravity.chatSignInInfo',
+          "Antigravity chats have their own sign-in. Signing in to the agy CLI doesn't sign you in here."
+        )}
+      </TooltipContent>
+    </Tooltip>
+  )
+}
+
 /** One host's chat sign-in as both Settings layouts show it. `signedOut` is the line for a host
  *  that answered it is not signed in; `unanswered` stands in while it has nothing else to say, as a
  *  host learns its sign-in only when a chat starts or asks to sign in. */
@@ -325,15 +345,18 @@ export function AntigravityChatSignInRow(props: {
             </Button>
           </div>
         ) : (
-          <Button
-            size="xs"
-            // Signed in, the button only switches account, so it steps back from the primary.
-            variant={signIn.action === 'changeAccount' ? 'outline' : 'default'}
-            disabled={signIn.signInDisabled}
-            onClick={signIn.start}
-          >
-            {signIn.actionLabel}
-          </Button>
+          <div className="flex shrink-0 items-center gap-1">
+            <AntigravityChatSignInInfo />
+            <Button
+              size="xs"
+              // Signed in, the button only switches account, so it steps back from the primary.
+              variant={signIn.action === 'changeAccount' ? 'outline' : 'default'}
+              disabled={signIn.signInDisabled}
+              onClick={signIn.start}
+            >
+              {signIn.actionLabel}
+            </Button>
+          </div>
         )}
       </div>
       {url && <PastedAddressForm pending={signIn.pending} send={signIn.send} />}
diff --git a/src/renderer/src/components/settings/AntigravityProviderSignInArea.tsx b/src/renderer/src/components/settings/AntigravityProviderSignInArea.tsx
index 25fba3d906f9..3cc2996f2049 100644
--- a/src/renderer/src/components/settings/AntigravityProviderSignInArea.tsx
+++ b/src/renderer/src/components/settings/AntigravityProviderSignInArea.tsx
@@ -5,6 +5,7 @@ import type { RuntimeClientTarget } from '../../../../shared/runtime-client-targ
 import { LoadingSpinner } from '../LoadingSpinner'
 import { Button } from '../ui/button'
 import {
+  AntigravityChatSignInInfo,
   PastedAddressForm,
   antigravityChatSignInBlocked,
   useAntigravityChatSignInControls
@@ -85,15 +86,18 @@ export function AntigravityProviderSignInArea(props: {
             </Button>
           </div>
         ) : (
-          <Button
-            size="xs"
-            // Signed in, the button only switches account, so it steps back further.
-            variant={signIn.action === 'changeAccount' ? 'ghost' : 'outline'}
-            disabled={signIn.signInDisabled}
-            onClick={signIn.start}
-          >
-            {signIn.actionLabel}
-          </Button>
+          <div className="flex shrink-0 items-center gap-1">
+            <AntigravityChatSignInInfo />
+            <Button
+              size="xs"
+              // Signed in, the button only switches account, so it steps back further.
+              variant={signIn.action === 'changeAccount' ? 'ghost' : 'outline'}
+              disabled={signIn.signInDisabled}
+              onClick={signIn.start}
+            >
+              {signIn.actionLabel}
+            </Button>
+          </div>
         )}
       </div>
       {url && <PastedAddressForm pending={signIn.pending} send={signIn.send} />}
diff --git a/src/renderer/src/i18n/locales/en.json b/src/renderer/src/i18n/locales/en.json
index d735840f6df7..0afca3021bd8 100644
--- a/src/renderer/src/i18n/locales/en.json
+++ b/src/renderer/src/i18n/locales/en.json
@@ -20092,6 +20092,8 @@
       "chatTitle": "Antigravity chats",
       "chatDescription": "Chats use their own Antigravity sign-in, separate from your agy account above. Sign in once on this device.",
       "chatSignIn": "Sign in",
+      "chatSignInInfoLabel": "About Antigravity sign-in",
+      "chatSignInInfo": "Antigravity chats have their own sign-in. Signing in to the agy CLI doesn't sign you in here.",
       "chatChangeAccount": "Change account",
       "chatRetry": "Retry sign-in",
       "chatCancel": "Cancel",
diff --git a/src/renderer/src/i18n/locales/es.json b/src/renderer/src/i18n/locales/es.json
index e57e14b9d160..72e3dc573ab3 100644
--- a/src/renderer/src/i18n/locales/es.json
+++ b/src/renderer/src/i18n/locales/es.json
@@ -19694,6 +19694,8 @@
       "chatTitle": "Chats de Antigravity",
       "chatDescription": "Los chats usan su propio inicio de sesión de Antigravity, independiente de tu cuenta de agy de arriba. Inicia sesión una vez en este dispositivo.",
       "chatSignIn": "Iniciar sesión",
+      "chatSignInInfoLabel": "Acerca del inicio de sesión de Antigravity",
+      "chatSignInInfo": "Los chats de Antigravity tienen su propio inicio de sesión. Iniciar sesión en la CLI de agy no inicia sesión aquí.",
       "chatChangeAccount": "Cambiar de cuenta",
       "chatRetry": "Reintentar inicio de sesión",
       "chatCancel": "Cancelar",
diff --git a/src/renderer/src/i18n/locales/fr.json b/src/renderer/src/i18n/locales/fr.json
index 7571c2be53b7..e735104b3e56 100644
--- a/src/renderer/src/i18n/locales/fr.json
+++ b/src/renderer/src/i18n/locales/fr.json
@@ -19851,6 +19851,8 @@
       "chatTitle": "Discussions Antigravity",
       "chatDescription": "Les discussions utilisent leur propre connexion Antigravity, distincte de votre compte agy ci-dessus. Connectez-vous une seule fois sur cet appareil.",
       "chatSignIn": "Se connecter",
+      "chatSignInInfoLabel": "À propos de la connexion Antigravity",
+      "chatSignInInfo": "Les chats Antigravity ont leur propre connexion. Se connecter à la CLI agy ne vous connecte pas ici.",
       "chatChangeAccount": "Changer de compte",
       "chatRetry": "Réessayer la connexion",
       "chatCancel": "Annuler",
diff --git a/src/renderer/src/i18n/locales/ja.json b/src/renderer/src/i18n/locales/ja.json
index 4c88d1d25949..8f7b5f4dea76 100644
--- a/src/renderer/src/i18n/locales/ja.json
+++ b/src/renderer/src/i18n/locales/ja.json
@@ -19851,6 +19851,8 @@
       "chatTitle": "Antigravity チャット",
       "chatDescription": "チャットは上の agy アカウントとは別の、独自の Antigravity サインインを使用します。このデバイスで一度サインインしてください。",
       "chatSignIn": "サインイン",
+      "chatSignInInfoLabel": "Antigravity のサインインについて",
+      "chatSignInInfo": "Antigravity チャットには専用のサインインがあります。agy CLI にサインインしても、ここではサインインされません。",
       "chatChangeAccount": "アカウントを変更",
       "chatRetry": "サインインを再試行",
       "chatCancel": "キャンセル",
diff --git a/src/renderer/src/i18n/locales/ko.json b/src/renderer/src/i18n/locales/ko.json
index 6bcc6bddc12e..4aea15541189 100644
--- a/src/renderer/src/i18n/locales/ko.json
+++ b/src/renderer/src/i18n/locales/ko.json
@@ -19851,6 +19851,8 @@
       "chatTitle": "Antigravity 채팅",
       "chatDescription": "채팅은 위의 agy 계정과 별개인 자체 Antigravity 로그인을 사용합니다. 이 기기에서 한 번 로그인하세요.",
       "chatSignIn": "로그인",
+      "chatSignInInfoLabel": "Antigravity 로그인 정보",
+      "chatSignInInfo": "Antigravity 채팅은 별도로 로그인합니다. agy CLI에 로그인해도 여기에는 로그인되지 않습니다.",
       "chatChangeAccount": "계정 변경",
       "chatRetry": "로그인 다시 시도",
       "chatCancel": "취소",
diff --git a/src/renderer/src/i18n/locales/zh.json b/src/renderer/src/i18n/locales/zh.json
index aa269aa3e3b5..d47bfd693968 100644
--- a/src/renderer/src/i18n/locales/zh.json
+++ b/src/renderer/src/i18n/locales/zh.json
@@ -19851,6 +19851,8 @@
       "chatTitle": "Antigravity 聊天",
       "chatDescription": "聊天使用自己的 Antigravity 登录，与上方的 agy 帐户分开。在此设备上登录一次即可。",
       "chatSignIn": "登录",
+      "chatSignInInfoLabel": "关于 Antigravity 登录",
+      "chatSignInInfo": "Antigravity 聊天有单独的登录。登录 agy CLI 不会在这里登录。",
       "chatChangeAccount": "更换帐户",
       "chatRetry": "重试登录",
       "chatCancel": "取消",