diff --git a/src/vs/workbench/api/common/extHost.api.impl.ts b/src/vs/workbench/api/common/extHost.api.impl.ts
index 2b49b0f59d6..a1591ae8ad3 100644
--- a/src/vs/workbench/api/common/extHost.api.impl.ts
+++ b/src/vs/workbench/api/common/extHost.api.impl.ts
@@ -1706,6 +1706,7 @@ export function createApiFactoryAndRegisterActors(accessor: ServicesAccessor): I
 			ChatResponseAnchorPart: extHostTypes.ChatResponseAnchorPart,
 			ChatResponseProgressPart: extHostTypes.ChatResponseProgressPart,
 			ChatResponseReferencePart: extHostTypes.ChatResponseReferencePart,
+			ChatResponseWarningPart: extHostTypes.ChatResponseWarningPart,
 			ChatResponseTextEditPart: extHostTypes.ChatResponseTextEditPart,
 			ChatResponseMarkdownWithVulnerabilitiesPart: extHostTypes.ChatResponseMarkdownWithVulnerabilitiesPart,
 			ChatResponseCommandButtonPart: extHostTypes.ChatResponseCommandButtonPart,
diff --git a/src/vs/workbench/api/common/extHostChatAgents2.ts b/src/vs/workbench/api/common/extHostChatAgents2.ts
index 82a25240fe4..165da541365 100644
--- a/src/vs/workbench/api/common/extHostChatAgents2.ts
+++ b/src/vs/workbench/api/common/extHostChatAgents2.ts
@@ -123,6 +123,13 @@ class ChatAgentResponseStream {
 					_report(dto);
 					return this;
 				},
+				warning(value) {
+					throwIfDone(this.progress);
+					const part = new extHostTypes.ChatResponseWarningPart(value);
+					const dto = typeConvert.ChatResponseWarningPart.from(part);
+					_report(dto);
+					return this;
+				},
 				reference(value, iconPath) {
 					throwIfDone(this.reference);
 
diff --git a/src/vs/workbench/api/common/extHostTypeConverters.ts b/src/vs/workbench/api/common/extHostTypeConverters.ts
index bb32ca47812..70e3a4c5167 100644
--- a/src/vs/workbench/api/common/extHostTypeConverters.ts
+++ b/src/vs/workbench/api/common/extHostTypeConverters.ts
@@ -39,7 +39,7 @@ import { DEFAULT_EDITOR_ASSOCIATION, SaveReason } from 'vs/workbench/common/edit
 import { IViewBadge } from 'vs/workbench/common/views';
 import { ChatAgentLocation, IChatAgentRequest, IChatAgentResult } from 'vs/workbench/contrib/chat/common/chatAgents';
 import { IChatRequestVariableEntry } from 'vs/workbench/contrib/chat/common/chatModel';
-import { IChatAgentDetection, IChatAgentMarkdownContentWithVulnerability, IChatCommandButton, IChatContentInlineReference, IChatContentReference, IChatFollowup, IChatMarkdownContent, IChatProgressMessage, IChatTextEdit, IChatTreeData, IChatUserActionEvent } from 'vs/workbench/contrib/chat/common/chatService';
+import { IChatAgentDetection, IChatAgentMarkdownContentWithVulnerability, IChatCommandButton, IChatContentInlineReference, IChatContentReference, IChatFollowup, IChatMarkdownContent, IChatProgressMessage, IChatTextEdit, IChatTreeData, IChatUserActionEvent, IChatWarningMessage } from 'vs/workbench/contrib/chat/common/chatService';
 import { IChatRequestVariableValue } from 'vs/workbench/contrib/chat/common/chatVariables';
 import * as chatProvider from 'vs/workbench/contrib/chat/common/languageModels';
 import { DebugTreeItemCollapsibleState, IDebugVisualizationTreeItem } from 'vs/workbench/contrib/debug/common/debug';
@@ -2463,6 +2463,18 @@ export namespace ChatResponseProgressPart {
 	}
 }
 
+export namespace ChatResponseWarningPart {
+	export function from(part: vscode.ChatResponseWarningPart): Dto<IChatWarningMessage> {
+		return {
+			kind: 'warning',
+			content: MarkdownString.from(part.value)
+		};
+	}
+	export function to(part: Dto<IChatWarningMessage>): vscode.ChatResponseWarningPart {
+		return new types.ChatResponseWarningPart(part.content.value);
+	}
+}
+
 export namespace ChatResponseCommandButtonPart {
 	export function from(part: vscode.ChatResponseCommandButtonPart, commandsConverter: CommandsConverter, commandDisposables: DisposableStore): Dto<IChatCommandButton> {
 		// If the command isn't in the converter, then this session may have been restored, and the command args don't exist anymore
diff --git a/src/vs/workbench/api/common/extHostTypes.ts b/src/vs/workbench/api/common/extHostTypes.ts
index 362ae439933..1175df5453c 100644
--- a/src/vs/workbench/api/common/extHostTypes.ts
+++ b/src/vs/workbench/api/common/extHostTypes.ts
@@ -4362,6 +4362,17 @@ export class ChatResponseProgressPart {
 	}
 }
 
+export class ChatResponseWarningPart {
+	value: vscode.MarkdownString;
+	constructor(value: string | vscode.MarkdownString) {
+		if (typeof value !== 'string' && value.isTrusted === true) {
+			throw new Error('The boolean form of MarkdownString.isTrusted is NOT supported for chat participants.');
+		}
+
+		this.value = typeof value === 'string' ? new MarkdownString(value) : value;
+	}
+}
+
 export class ChatResponseCommandButtonPart {
 	value: vscode.Command;
 	constructor(value: vscode.Command) {
diff --git a/src/vs/workbench/contrib/chat/browser/chatListRenderer.ts b/src/vs/workbench/contrib/chat/browser/chatListRenderer.ts
index ed6193be46a..0c1a447222a 100644
--- a/src/vs/workbench/contrib/chat/browser/chatListRenderer.ts
+++ b/src/vs/workbench/contrib/chat/browser/chatListRenderer.ts
@@ -67,7 +67,7 @@ import { ChatAgentLocation, IChatAgentMetadata, IChatAgentNameService } from 'vs
 import { CONTEXT_CHAT_RESPONSE_SUPPORT_ISSUE_REPORTING, CONTEXT_REQUEST, CONTEXT_RESPONSE, CONTEXT_RESPONSE_DETECTED_AGENT_COMMAND, CONTEXT_RESPONSE_FILTERED, CONTEXT_RESPONSE_VOTE } from 'vs/workbench/contrib/chat/common/chatContextKeys';
 import { IChatProgressRenderableResponseContent, IChatTextEditGroup } from 'vs/workbench/contrib/chat/common/chatModel';
 import { chatAgentLeader, chatSubcommandLeader } from 'vs/workbench/contrib/chat/common/chatParserTypes';
-import { IChatCommandButton, IChatContentReference, IChatFollowup, IChatProgressMessage, IChatResponseProgressFileTreeData, InteractiveSessionVoteDirection } from 'vs/workbench/contrib/chat/common/chatService';
+import { IChatCommandButton, IChatContentReference, IChatFollowup, IChatProgressMessage, IChatResponseProgressFileTreeData, IChatWarningMessage, InteractiveSessionVoteDirection } from 'vs/workbench/contrib/chat/common/chatService';
 import { IChatVariablesService } from 'vs/workbench/contrib/chat/common/chatVariables';
 import { IChatProgressMessageRenderData, IChatRenderData, IChatResponseMarkdownRenderData, IChatResponseViewModel, IChatWelcomeMessageViewModel, isRequestVM, isResponseVM, isWelcomeVM } from 'vs/workbench/contrib/chat/common/chatViewModel';
 import { IWordCountResult, getNWords } from 'vs/workbench/contrib/chat/common/chatWordCounter';
@@ -511,7 +511,9 @@ export class ChatListItemRenderer extends Disposable implements ITreeRenderer<Ch
 					: data.kind === 'progressMessage' && onlyProgressMessagesAfterI(value, index) ? this.renderProgressMessage(data, false) // TODO render command
 						: data.kind === 'command' ? this.renderCommandButton(element, data)
 							: data.kind === 'textEditGroup' ? this.renderTextEdit(element, data, templateData)
-								: undefined;
+								: data.kind === 'warning' ? this.renderWarning(element, data)
+									: undefined;
+
 			if (result) {
 				templateData.value.appendChild(result.element);
 				templateData.elementDisposables.add(result);
@@ -919,6 +921,17 @@ export class ChatListItemRenderer extends Disposable implements ITreeRenderer<Ch
 		};
 	}
 
+	private renderWarning(element: ChatTreeItem, chatWarning: IChatWarningMessage): IMarkdownRenderResult | undefined {
+		const container = $('.chat-warning');
+		container.appendChild($('.chat-warning-codicon', undefined, renderIcon(Codicon.warning)));
+		const markdownContent = this.renderer.render(chatWarning.content);
+		container.appendChild(markdownContent.element);
+		return {
+			element: container,
+			dispose() { markdownContent.dispose(); }
+		};
+	}
+
 	private renderTextEdit(element: ChatTreeItem, chatTextEdit: IChatTextEditGroup, templateData: IChatListItemTemplate): IMarkdownRenderResult | undefined {
 
 		// TODO@jrieken move this into the CompareCodeBlock and properly say what kind of changes happen
diff --git a/src/vs/workbench/contrib/chat/browser/media/chat.css b/src/vs/workbench/contrib/chat/browser/media/chat.css
index d0a0a088e9c..e155c3304e2 100644
--- a/src/vs/workbench/contrib/chat/browser/media/chat.css
+++ b/src/vs/workbench/contrib/chat/browser/media/chat.css
@@ -410,6 +410,17 @@
 	padding-inline-start: unset;
 }
 
+.chat-warning .chat-warning-codicon {
+	margin-left: 3px;
+	display: flex;
+	align-items: start;
+	gap: 6px;
+}
+
+.interactive-item-container .value .chat-warning .rendered-markdown p {
+	margin: 0;
+}
+
 .interactive-response .interactive-response-error-details {
 	display: flex;
 	align-items: start;
@@ -420,10 +431,18 @@
 	margin-bottom: 0px;
 }
 
+.chat-warning .chat-warning-codicon .codicon {
+	margin-top: 2px;
+}
+
 .interactive-response .interactive-response-error-details .codicon {
 	margin-top: 1px;
 }
 
+.chat-warning .chat-warning-codicon .codicon-warning {
+	color: var(--vscode-notificationsWarningIcon-foreground) !important; /* Have to override default styles which apply to all lists */
+}
+
 .interactive-response .interactive-response-error-details .codicon-error {
 	color: var(--vscode-errorForeground) !important; /* Have to override default styles which apply to all lists */
 }
@@ -596,6 +615,7 @@
 }
 
 .interactive-response-progress-tree,
+.interactive-item-container .chat-warning,
 .interactive-session .chat-used-context-list {
 	border: 1px solid var(--vscode-chat-requestBorder);
 	border-radius: 4px;
@@ -669,6 +689,12 @@
 	margin-bottom: 16px;
 }
 
+.interactive-item-container .chat-warning {
+	display: flex;
+	flex-direction: row;
+	gap: 6px;
+}
+
 .interactive-item-container .chat-command-button .monaco-button {
 	text-align: left;
 	width: initial;
diff --git a/src/vs/workbench/contrib/chat/common/chatModel.ts b/src/vs/workbench/contrib/chat/common/chatModel.ts
index 6c400c395ac..7d44af6bba5 100644
--- a/src/vs/workbench/contrib/chat/common/chatModel.ts
+++ b/src/vs/workbench/contrib/chat/common/chatModel.ts
@@ -20,7 +20,7 @@ import { IInstantiationService } from 'vs/platform/instantiation/common/instanti
 import { ILogService } from 'vs/platform/log/common/log';
 import { ChatAgentLocation, IChatAgentCommand, IChatAgentData, IChatAgentHistoryEntry, IChatAgentRequest, IChatAgentResult, IChatAgentService } from 'vs/workbench/contrib/chat/common/chatAgents';
 import { ChatRequestTextPart, IParsedChatRequest, getPromptText, reviveParsedChatRequest } from 'vs/workbench/contrib/chat/common/chatParserTypes';
-import { IChatAgentMarkdownContentWithVulnerability, IChatCommandButton, IChatContentInlineReference, IChatContentReference, IChatFollowup, IChatMarkdownContent, IChatProgress, IChatProgressMessage, IChatResponseProgressFileTreeData, IChatTextEdit, IChatTreeData, IChatUsedContext, InteractiveSessionVoteDirection, isIUsedContext } from 'vs/workbench/contrib/chat/common/chatService';
+import { IChatAgentMarkdownContentWithVulnerability, IChatCommandButton, IChatContentInlineReference, IChatContentReference, IChatFollowup, IChatMarkdownContent, IChatProgress, IChatProgressMessage, IChatResponseProgressFileTreeData, IChatTextEdit, IChatTreeData, IChatUsedContext, IChatWarningMessage, InteractiveSessionVoteDirection, isIUsedContext } from 'vs/workbench/contrib/chat/common/chatService';
 import { IChatRequestVariableValue } from 'vs/workbench/contrib/chat/common/chatVariables';
 
 export interface IChatPromptVariableData {
@@ -66,6 +66,7 @@ export type IChatProgressResponseContent =
 	| IChatContentInlineReference
 	| IChatProgressMessage
 	| IChatCommandButton
+	| IChatWarningMessage
 	| IChatTextEditGroup;
 
 export type IChatProgressRenderableResponseContent = Exclude<IChatProgressResponseContent, IChatContentInlineReference | IChatAgentMarkdownContentWithVulnerability>;
@@ -229,6 +230,8 @@ export class Response implements IResponse {
 				return '';
 			} else if (part.kind === 'progressMessage') {
 				return '';
+			} else if (part.kind === 'warning') {
+				return '';
 			} else {
 				return part.content.value;
 			}
@@ -762,7 +765,7 @@ export class ChatModel extends Disposable implements IChatModel {
 			throw new Error('acceptResponseProgress: Adding progress to a completed response');
 		}
 
-		if (progress.kind === 'markdownContent' || progress.kind === 'treeData' || progress.kind === 'inlineReference' || progress.kind === 'markdownVuln' || progress.kind === 'progressMessage' || progress.kind === 'command' || progress.kind === 'textEdit') {
+		if (progress.kind === 'markdownContent' || progress.kind === 'treeData' || progress.kind === 'inlineReference' || progress.kind === 'markdownVuln' || progress.kind === 'progressMessage' || progress.kind === 'command' || progress.kind === 'textEdit' || progress.kind === 'warning') {
 			request.response.updateContent(progress, quiet);
 		} else if (progress.kind === 'usedContext' || progress.kind === 'reference') {
 			request.response.applyReference(progress);
diff --git a/src/vs/workbench/contrib/chat/common/chatService.ts b/src/vs/workbench/contrib/chat/common/chatService.ts
index 45b36d23700..1ea2e62094b 100644
--- a/src/vs/workbench/contrib/chat/common/chatService.ts
+++ b/src/vs/workbench/contrib/chat/common/chatService.ts
@@ -106,6 +106,11 @@ export interface IChatProgressMessage {
 	kind: 'progressMessage';
 }
 
+export interface IChatWarningMessage {
+	content: IMarkdownString;
+	kind: 'warning';
+}
+
 export interface IChatAgentVulnerabilityDetails {
 	title: string;
 	description: string;
@@ -138,6 +143,7 @@ export type IChatProgress =
 	| IChatAgentDetection
 	| IChatProgressMessage
 	| IChatCommandButton
+	| IChatWarningMessage
 	| IChatTextEdit;
 
 export interface IChatFollowup {
diff --git a/src/vscode-dts/vscode.proposed.chatParticipant.d.ts b/src/vscode-dts/vscode.proposed.chatParticipant.d.ts
index be004ff4a91..6f7c51fef2a 100644
--- a/src/vscode-dts/vscode.proposed.chatParticipant.d.ts
+++ b/src/vscode-dts/vscode.proposed.chatParticipant.d.ts
@@ -351,6 +351,15 @@ declare module 'vscode' {
 		 */
 		reference(value: Uri | Location | { variableName: string; value?: Uri | Location }, iconPath?: ThemeIcon): ChatResponseStream;
 
+		/**
+		 * Push a warning to this stream. Short-hand for
+		 * `push(new ChatResponseWarningPart(message))`.
+		 *
+		 * @param message A warning message
+		 * @returns This stream.
+		 */
+		warning(message: string | MarkdownString): ChatResponseStream;
+
 		/**
 		 * Pushes a part to this stream.
 		 *
@@ -401,11 +410,16 @@ declare module 'vscode' {
 		constructor(value: Command);
 	}
 
+	export class ChatResponseWarningPart {
+		value: MarkdownString;
+		constructor(value: string | MarkdownString);
+	}
+
 	/**
 	 * Represents the different chat response types.
 	 */
 	export type ChatResponsePart = ChatResponseMarkdownPart | ChatResponseFileTreePart | ChatResponseAnchorPart
-		| ChatResponseProgressPart | ChatResponseReferencePart | ChatResponseCommandButtonPart;
+		| ChatResponseProgressPart | ChatResponseReferencePart | ChatResponseCommandButtonPart | ChatResponseWarningPart;
 
 
 	export namespace chat {