diff --git a/packages/frontend/core/src/blocksuite/ai/chat-panel/chat-config.ts b/packages/frontend/core/src/blocksuite/ai/chat-panel/chat-config.ts
index 60bea05e49..8cfde6e69f 100644
--- a/packages/frontend/core/src/blocksuite/ai/chat-panel/chat-config.ts
+++ b/packages/frontend/core/src/blocksuite/ai/chat-panel/chat-config.ts
@@ -3,6 +3,17 @@ import type { LinkedMenuGroup } from '@blocksuite/affine/blocks';
 import type { Store } from '@blocksuite/affine/store';
 import type { Signal } from '@preact/signals-core';
 
+export interface AppSidebarConfig {
+  getWidth: () => {
+    signal: Signal<number | undefined>;
+    cleanup: () => void;
+  };
+  isOpen: () => {
+    signal: Signal<boolean | undefined>;
+    cleanup: () => void;
+  };
+}
+
 export interface AINetworkSearchConfig {
   visible: Signal<boolean | undefined>;
   enabled: Signal<boolean | undefined>;
diff --git a/packages/frontend/core/src/blocksuite/ai/chat-panel/chat-panel-messages.ts b/packages/frontend/core/src/blocksuite/ai/chat-panel/chat-panel-messages.ts
index 0290317ee9..0a574d8df9 100644
--- a/packages/frontend/core/src/blocksuite/ai/chat-panel/chat-panel-messages.ts
+++ b/packages/frontend/core/src/blocksuite/ai/chat-panel/chat-panel-messages.ts
@@ -8,7 +8,7 @@ import {
 } from '@blocksuite/affine/blocks';
 import { WithDisposable } from '@blocksuite/affine/global/utils';
 import type { BaseSelection } from '@blocksuite/affine/store';
-import { css, html, nothing } from 'lit';
+import { css, html, nothing, type PropertyValues } from 'lit';
 import { property, query, state } from 'lit/decorators.js';
 import { repeat } from 'lit/directives/repeat.js';
 import { debounce } from 'lodash-es';
@@ -196,17 +196,6 @@ export class ChatPanelMessages extends WithDisposable(ShadowlessElement) {
     return this.messagesContainer;
   }
 
-  get showDownIndicator() {
-    if (!this.messagesContainer) return false;
-    const { clientHeight, scrollTop, scrollHeight } = this.messagesContainer;
-    const canScrollDown = scrollHeight - scrollTop - clientHeight > 200;
-    const showDownIndicator =
-      canScrollDown &&
-      this.chatContextValue.items.length > 0 &&
-      this.chatContextValue.status !== 'transmitting';
-    return showDownIndicator;
-  }
-
   private _renderAIOnboarding() {
     return this.isLoading ||
       !this.host?.doc.get(FeatureFlagService).getFlag('enable_ai_onboarding')
@@ -239,6 +228,11 @@ export class ChatPanelMessages extends WithDisposable(ShadowlessElement) {
     100
   );
 
+  private readonly _onDownIndicatorClick = () => {
+    this.canScrollDown = false;
+    this.scrollToEnd();
+  };
+
   protected override render() {
     const { items } = this.chatContextValue;
     const { isLoading } = this;
@@ -251,6 +245,11 @@ export class ChatPanelMessages extends WithDisposable(ShadowlessElement) {
       );
     });
 
+    const showDownIndicator =
+      this.canScrollDown &&
+      filteredItems.length > 0 &&
+      this.chatContextValue.status !== 'transmitting';
+
     return html`
       <div
         class="chat-panel-messages"
@@ -284,8 +283,8 @@ export class ChatPanelMessages extends WithDisposable(ShadowlessElement) {
               }
             )}
       </div>
-      ${this.showDownIndicator && filteredItems.length > 0
-        ? html`<div class="down-indicator" @click=${this.scrollToEnd}>
+      ${showDownIndicator && filteredItems.length > 0
+        ? html`<div class="down-indicator" @click=${this._onDownIndicatorClick}>
             ${DownArrowIcon}
           </div>`
         : nothing}
@@ -329,6 +328,12 @@ export class ChatPanelMessages extends WithDisposable(ShadowlessElement) {
     );
   }
 
+  protected override updated(_changedProperties: PropertyValues) {
+    if (_changedProperties.has('isLoading')) {
+      this.canScrollDown = false;
+    }
+  }
+
   renderItem(item: ChatItem, isLast: boolean) {
     const { status, error } = this.chatContextValue;
     const { host } = this;
diff --git a/packages/frontend/core/src/blocksuite/ai/chat-panel/index.ts b/packages/frontend/core/src/blocksuite/ai/chat-panel/index.ts
index 3c67488854..70a4ecc85d 100644
--- a/packages/frontend/core/src/blocksuite/ai/chat-panel/index.ts
+++ b/packages/frontend/core/src/blocksuite/ai/chat-panel/index.ts
@@ -7,11 +7,12 @@ import {
   NotificationProvider,
   type SpecBuilder,
 } from '@blocksuite/affine/blocks';
-import { WithDisposable } from '@blocksuite/affine/global/utils';
+import { SignalWatcher, WithDisposable } from '@blocksuite/affine/global/utils';
 import type { Store } from '@blocksuite/affine/store';
 import { css, html, type PropertyValues } from 'lit';
 import { property, state } from 'lit/decorators.js';
 import { createRef, type Ref, ref } from 'lit/directives/ref.js';
+import { styleMap } from 'lit/directives/style-map.js';
 import { throttle } from 'lodash-es';
 
 import { AIHelpIcon, SmallHintIcon } from '../_common/icons';
@@ -23,6 +24,7 @@ import {
 } from '../utils/selection-utils';
 import type {
   AINetworkSearchConfig,
+  AppSidebarConfig,
   DocDisplayConfig,
   DocSearchMenuConfig,
 } from './chat-config';
@@ -47,7 +49,9 @@ const DEFAULT_CHAT_CONTEXT_VALUE: ChatContextValue = {
   markdown: '',
 };
 
-export class ChatPanel extends WithDisposable(ShadowlessElement) {
+export class ChatPanel extends SignalWatcher(
+  WithDisposable(ShadowlessElement)
+) {
   static override styles = css`
     chat-panel {
       width: 100%;
@@ -56,8 +60,6 @@ export class ChatPanel extends WithDisposable(ShadowlessElement) {
     .chat-panel-container {
       display: flex;
       flex-direction: column;
-      padding: 0 16px;
-      padding-top: 8px;
       height: 100%;
     }
 
@@ -241,6 +243,9 @@ export class ChatPanel extends WithDisposable(ShadowlessElement) {
   @property({ attribute: false })
   accessor networkSearchConfig!: AINetworkSearchConfig;
 
+  @property({ attribute: false })
+  accessor appSidebarConfig!: AppSidebarConfig;
+
   @property({ attribute: false })
   accessor docSearchMenuConfig!: DocSearchMenuConfig;
 
@@ -296,6 +301,9 @@ export class ChatPanel extends WithDisposable(ShadowlessElement) {
 
   private readonly _initPanel = async () => {
     try {
+      const isOpen = !!this.appSidebarConfig.isOpen().signal.value;
+      if (!isOpen) return;
+
       const userId = (await AIProvider.userInfo)?.id;
       if (!userId) return;
 
@@ -326,6 +334,7 @@ export class ChatPanel extends WithDisposable(ShadowlessElement) {
       this._chatSessionId = null;
       this._chatContextId = null;
       this.chatContextValue = DEFAULT_CHAT_CONTEXT_VALUE;
+      this.isLoading = true;
 
       requestAnimationFrame(async () => {
         await this._initPanel();
@@ -365,6 +374,14 @@ export class ChatPanel extends WithDisposable(ShadowlessElement) {
         })
         .catch(console.error);
     }
+
+    this._disposables.add(
+      this.appSidebarConfig.isOpen().signal.subscribe(isOpen => {
+        if (isOpen && this.isLoading) {
+          this._initPanel().catch(console.error);
+        }
+      })
+    );
   }
 
   override connectedCallback() {
@@ -414,7 +431,13 @@ export class ChatPanel extends WithDisposable(ShadowlessElement) {
   };
 
   override render() {
-    return html` <div class="chat-panel-container">
+    const panelWidth = this.appSidebarConfig.getWidth().signal.value;
+    const style = styleMap({
+      padding:
+        panelWidth && panelWidth > 540 ? '8px 24px 0 24px' : '8px 12px 0 12px',
+    });
+
+    return html`<div class="chat-panel-container" style=${style}>
       <div class="chat-panel-title">
         <div>AFFiNE AI</div>
         <div
diff --git a/packages/frontend/core/src/desktop/pages/workspace/detail-page/tabs/chat.tsx b/packages/frontend/core/src/desktop/pages/workspace/detail-page/tabs/chat.tsx
index d35f2965a1..bb8c30f0c2 100644
--- a/packages/frontend/core/src/desktop/pages/workspace/detail-page/tabs/chat.tsx
+++ b/packages/frontend/core/src/desktop/pages/workspace/detail-page/tabs/chat.tsx
@@ -4,6 +4,7 @@ import { enableFootnoteConfigExtension } from '@affine/core/blocksuite/extension
 import { AINetworkSearchService } from '@affine/core/modules/ai-button/services/network-search';
 import { DocDisplayMetaService } from '@affine/core/modules/doc-display-meta';
 import { DocSearchMenuService } from '@affine/core/modules/doc-search-menu/services';
+import { WorkbenchService } from '@affine/core/modules/workbench';
 import { WorkspaceService } from '@affine/core/modules/workspace';
 import {
   createSignalFromObservable,
@@ -58,6 +59,17 @@ export const EditorChatPanel = forwardRef(function EditorChatPanel(
       const docDisplayMetaService = framework.get(DocDisplayMetaService);
       const workspaceService = framework.get(WorkspaceService);
       const docSearchMenuService = framework.get(DocSearchMenuService);
+      const workbench = framework.get(WorkbenchService).workbench;
+      chatPanelRef.current.appSidebarConfig = {
+        getWidth: () => {
+          const width$ = workbench.sidebarWidth$;
+          return createSignalFromObservable(width$, 0);
+        },
+        isOpen: () => {
+          const open$ = workbench.sidebarOpen$;
+          return createSignalFromObservable(open$, true);
+        },
+      };
       chatPanelRef.current.networkSearchConfig = {
         visible: searchService.visible,
         enabled: searchService.enabled,