diff --git a/src/vs/base/browser/ui/button/button.ts b/src/vs/base/browser/ui/button/button.ts
index 5b32ddc9d85..8b7fc2d9b33 100644
--- a/src/vs/base/browser/ui/button/button.ts
+++ b/src/vs/base/browser/ui/button/button.ts
@@ -351,10 +351,10 @@ export class Button extends Disposable implements IButton {
 	set checked(value: boolean) {
 		if (value) {
 			this._element.classList.add('checked');
-			this._element.setAttribute('aria-checked', 'true');
+			this._element.setAttribute('aria-pressed', 'true');
 		} else {
 			this._element.classList.remove('checked');
-			this._element.setAttribute('aria-checked', 'false');
+			this._element.setAttribute('aria-pressed', 'false');
 		}
 	}
 
diff --git a/src/vs/workbench/browser/parts/compositeBarActions.ts b/src/vs/workbench/browser/parts/compositeBarActions.ts
index 337ec9a0d4e..fe7bce2f083 100644
--- a/src/vs/workbench/browser/parts/compositeBarActions.ts
+++ b/src/vs/workbench/browser/parts/compositeBarActions.ts
@@ -237,11 +237,11 @@ export class CompositeBarActionViewItem extends BaseActionViewItem {
 			this.container.classList.add('icon');
 		}
 
+		// Use 'tab' inside tablist, 'button' for popup items outside tablist
+		const role = this.options.isTabList || !this.options.hasPopup ? 'tab' : 'button';
+		this.container.setAttribute('role', role);
 		if (this.options.hasPopup) {
-			this.container.setAttribute('role', 'button');
 			this.container.setAttribute('aria-haspopup', 'true');
-		} else {
-			this.container.setAttribute('role', 'tab');
 		}
 
 		// Try hard to prevent keyboard only focus feedback when using mouse
@@ -479,7 +479,7 @@ export class CompositeOverflowActivityActionViewItem extends CompositeBarActionV
 		@IConfigurationService configurationService: IConfigurationService,
 		@IKeybindingService keybindingService: IKeybindingService,
 	) {
-		super(action, { icon: true, colors, hasPopup: true, hoverOptions }, () => true, themeService, hoverService, configurationService, keybindingService);
+		super(action, { icon: true, colors, hasPopup: true, hoverOptions, isTabList: true }, () => true, themeService, hoverService, configurationService, keybindingService);
 	}
 
 	showMenu(): void {
diff --git a/src/vs/workbench/contrib/chat/browser/agentSessions/experiments/agentTitleBarStatusWidget.ts b/src/vs/workbench/contrib/chat/browser/agentSessions/experiments/agentTitleBarStatusWidget.ts
index b4d2442497f..d44024fa6de 100644
--- a/src/vs/workbench/contrib/chat/browser/agentSessions/experiments/agentTitleBarStatusWidget.ts
+++ b/src/vs/workbench/contrib/chat/browser/agentSessions/experiments/agentTitleBarStatusWidget.ts
@@ -749,7 +749,7 @@ export class AgentTitleBarStatusWidget extends BaseActionViewItem {
 		// Create dropdown action (empty label prevents default tooltip - we have our own hover)
 		const dropdownAction = toAction({
 			id: 'agentStatus.sparkle.dropdown',
-			label: '',
+			label: localize('agentStatus.sparkle.dropdown', "More Actions"),
 			run() { }
 		});
 
diff --git a/test/smoke/src/areas/accessibility/accessibility.test.ts b/test/smoke/src/areas/accessibility/accessibility.test.ts
index 9472218a82f..d6f02874590 100644
--- a/test/smoke/src/areas/accessibility/accessibility.test.ts
+++ b/test/smoke/src/areas/accessibility/accessibility.test.ts
@@ -3,14 +3,14 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
-import { Application, Logger } from '../../../../automation';
+import { Application, Logger, Quality } from '../../../../automation';
 import { installAllHandlers } from '../../utils';
 
-export function setup(logger: Logger, opts: { web?: boolean }) {
-	describe.skip('Accessibility', function () {
+export function setup(logger: Logger, opts: { web?: boolean }, quality: Quality) {
+	describe('Accessibility', function () {
 
 		// Increase timeout for accessibility scans
-		this.timeout(30 * 1000);
+		this.timeout(2 * 60 * 1000);
 
 		// Retry tests to minimize flakiness
 		this.retries(2);
@@ -38,7 +38,9 @@ export function setup(logger: Logger, opts: { web?: boolean }) {
 						// Monaco lists use aria-multiselectable on role="list" and aria-setsize/aria-posinset/aria-selected on role="dialog" rows
 						// These violations appear intermittently when notification lists or other dynamic lists are visible
 						// Note: patterns match against HTML string, not CSS selectors, so no leading dots
-						'aria-allowed-attr': ['monaco-list', 'monaco-list-row']
+						'aria-allowed-attr': ['monaco-list', 'monaco-list-row'],
+						// Monaco lists may temporarily contain dialog children during extension activation errors
+						'aria-required-children': ['monaco-list']
 					}
 				});
 			});
@@ -69,7 +71,7 @@ export function setup(logger: Logger, opts: { web?: boolean }) {
 		});
 
 		// Chat is not available in web mode
-		if (!opts.web) {
+		if (quality !== Quality.Dev && quality !== Quality.OSS && !opts.web) {
 			describe('Chat', function () {
 
 				it('chat panel has no accessibility violations', async function () {
@@ -87,6 +89,79 @@ export function setup(logger: Logger, opts: { web?: boolean }) {
 						}
 					});
 				});
+
+				// Chat response test requires gallery service which is only available in non-Dev/OSS builds
+				it('chat response has no accessibility violations', async function () {
+					// Disable retries for this test - it modifies settings and retries cause issues
+					this.retries(0);
+					// Extend timeout for this test since AI responses can take a while
+					this.timeout(3 * 60 * 1000);
+
+					// Enable anonymous chat access
+					await app.workbench.settingsEditor.addUserSetting('chat.allowAnonymousAccess', 'true');
+
+					// Open chat panel
+					await app.workbench.quickaccess.runCommand('workbench.action.chat.open');
+
+					// Wait for chat view to be visible
+					await app.workbench.chat.waitForChatView();
+
+					// Send a simple message
+					await app.workbench.chat.sendMessage('Create a simple hello.txt file with the text "Hello World"');
+
+					// Wait for the response to complete (1500 retries ~= 150 seconds at 100ms per retry)
+					await app.workbench.chat.waitForResponse(1500);
+
+					// Run accessibility check on the chat panel with the response
+					await app.code.driver.assertNoAccessibilityViolations({
+						selector: 'div[id="workbench.panel.chat"]',
+						excludeRules: {
+							// Links in chat welcome view show underline on hover/focus which axe-core static analysis cannot detect
+							'link-in-text-block': ['command:workbench.action.chat.generateInstructions'],
+							// Monaco lists use aria-multiselectable on role="list" and aria-selected on role="listitem"
+							// These are used intentionally for selection semantics even though technically not spec-compliant
+							'aria-allowed-attr': ['monaco-list', 'monaco-list-row'],
+							// Some icon buttons have empty aria-label during rendering
+							'aria-command-name': ['codicon-plus']
+						}
+					});
+				});
+
+				it('chat terminal tool response has no accessibility violations', async function () {
+					// Disable retries for this test
+					this.retries(0);
+					// Extend timeout for this test since AI responses can take a while
+					this.timeout(3 * 60 * 1000);
+
+					// Enable auto-approve for tools so terminal commands run automatically
+					await app.workbench.settingsEditor.addUserSetting('chat.tools.global.autoApprove', 'true');
+
+					// Open chat panel
+					await app.workbench.quickaccess.runCommand('workbench.action.chat.open');
+
+					// Wait for chat view to be visible
+					await app.workbench.chat.waitForChatView();
+
+					// Send a terminal command request
+					await app.workbench.chat.sendMessage('Run ls in the terminal');
+
+					// Wait for the response to complete (1500 retries ~= 150 seconds at 100ms per retry)
+					await app.workbench.chat.waitForResponse(1500);
+
+					// Run accessibility check on the chat panel with the response
+					await app.code.driver.assertNoAccessibilityViolations({
+						selector: 'div[id="workbench.panel.chat"]',
+						excludeRules: {
+							// Links in chat welcome view show underline on hover/focus which axe-core static analysis cannot detect
+							'link-in-text-block': ['command:workbench.action.chat.generateInstructions'],
+							// Monaco lists use aria-multiselectable on role="list" and aria-selected on role="listitem"
+							// These are used intentionally for selection semantics even though technically not spec-compliant
+							'aria-allowed-attr': ['monaco-list', 'monaco-list-row'],
+							// Some icon buttons have empty aria-label during rendering
+							'aria-command-name': ['codicon-plus']
+						}
+					});
+				});
 			});
 		}
 	});
diff --git a/test/smoke/src/main.ts b/test/smoke/src/main.ts
index 2360381fd52..15279bbd5a1 100644
--- a/test/smoke/src/main.ts
+++ b/test/smoke/src/main.ts
@@ -408,5 +408,5 @@ describe(`VSCode Smoke Tests (${opts.web ? 'Web' : 'Electron'})`, () => {
 	if (!opts.web && !opts.remote) { setupLaunchTests(logger); }
 	if (!opts.web) { setupChatTests(logger); }
 	if (!opts.web && quality === Quality.Insiders) { setupChatAnonymousTests(logger); }
-	setupAccessibilityTests(logger, opts);
+	setupAccessibilityTests(logger, opts, quality);
 });