diff --git a/src/vs/vscode.proposed.d.ts b/src/vs/vscode.proposed.d.ts
index 1a431a05af7..469ccb7db19 100644
--- a/src/vs/vscode.proposed.d.ts
+++ b/src/vs/vscode.proposed.d.ts
@@ -2754,4 +2754,15 @@ declare module 'vscode' {
 	}
 
 	//#endregion
+
+	//#region https://github.com/microsoft/vscode/issues/129053
+
+	export namespace env {
+		/**
+		 * The environment in which the app is embedded in. i.e. Desktop, Codespaces, Web.
+		 */
+		export const embedderIdentifier: string;
+	}
+
+	//#endregion
 }
diff --git a/src/vs/workbench/api/common/extHost.api.impl.ts b/src/vs/workbench/api/common/extHost.api.impl.ts
index bad876b57ff..151eb40e757 100644
--- a/src/vs/workbench/api/common/extHost.api.impl.ts
+++ b/src/vs/workbench/api/common/extHost.api.impl.ts
@@ -292,6 +292,7 @@ export function createApiFactoryAndRegisterActors(accessor: ServicesAccessor): I
 			get language() { return initData.environment.appLanguage; },
 			get appName() { return initData.environment.appName; },
 			get appRoot() { return initData.environment.appRoot?.fsPath ?? ''; },
+			get embedderIdentifier() { return initData.environment.embedderIdentifier; },
 			get uriScheme() { return initData.environment.appUriScheme; },
 			get clipboard(): vscode.Clipboard { return extHostClipboard.value; },
 			get shell() {
diff --git a/src/vs/workbench/api/common/extHost.protocol.ts b/src/vs/workbench/api/common/extHost.protocol.ts
index a97484b7f56..80c99f0707c 100644
--- a/src/vs/workbench/api/common/extHost.protocol.ts
+++ b/src/vs/workbench/api/common/extHost.protocol.ts
@@ -72,6 +72,7 @@ import { ILanguageStatus } from 'vs/editor/common/services/languageStatusService
 export interface IEnvironment {
 	isExtensionDevelopmentDebug: boolean;
 	appName: string;
+	embedderIdentifier: string;
 	appRoot?: URI;
 	appLanguage: string;
 	appUriScheme: string;
diff --git a/src/vs/workbench/services/extensions/browser/webWorkerExtensionHost.ts b/src/vs/workbench/services/extensions/browser/webWorkerExtensionHost.ts
index 4c005a12a7c..8869a8bcda4 100644
--- a/src/vs/workbench/services/extensions/browser/webWorkerExtensionHost.ts
+++ b/src/vs/workbench/services/extensions/browser/webWorkerExtensionHost.ts
@@ -375,6 +375,7 @@ export class WebWorkerExtensionHost extends Disposable implements IExtensionHost
 			environment: {
 				isExtensionDevelopmentDebug: this._environmentService.debugRenderer,
 				appName: this._productService.nameLong,
+				embedderIdentifier: this._productService.embedderIdentifier || 'web',
 				appUriScheme: this._productService.urlProtocol,
 				appLanguage: platform.language,
 				extensionDevelopmentLocationURI: this._environmentService.extensionDevelopmentLocationURI,
diff --git a/src/vs/workbench/services/extensions/common/remoteExtensionHost.ts b/src/vs/workbench/services/extensions/common/remoteExtensionHost.ts
index d238526f526..792273fe1ee 100644
--- a/src/vs/workbench/services/extensions/common/remoteExtensionHost.ts
+++ b/src/vs/workbench/services/extensions/common/remoteExtensionHost.ts
@@ -230,6 +230,7 @@ export class RemoteExtensionHost extends Disposable implements IExtensionHost {
 				isExtensionDevelopmentDebug,
 				appRoot: remoteInitData.appRoot,
 				appName: this._productService.nameLong,
+				embedderIdentifier: this._productService.embedderIdentifier || 'desktop',
 				appUriScheme: this._productService.urlProtocol,
 				appLanguage: platform.language,
 				extensionDevelopmentLocationURI: this._environmentService.extensionDevelopmentLocationURI,
diff --git a/src/vs/workbench/services/extensions/electron-browser/localProcessExtensionHost.ts b/src/vs/workbench/services/extensions/electron-browser/localProcessExtensionHost.ts
index e4ca4d6a380..31c18783080 100644
--- a/src/vs/workbench/services/extensions/electron-browser/localProcessExtensionHost.ts
+++ b/src/vs/workbench/services/extensions/electron-browser/localProcessExtensionHost.ts
@@ -470,6 +470,7 @@ export class LocalProcessExtensionHost implements IExtensionHost {
 				isExtensionDevelopmentDebug: this._isExtensionDevDebug,
 				appRoot: this._environmentService.appRoot ? URI.file(this._environmentService.appRoot) : undefined,
 				appName: this._productService.nameLong,
+				embedderIdentifier: this._productService.embedderIdentifier || 'desktop',
 				appUriScheme: this._productService.urlProtocol,
 				appLanguage: platform.language,
 				extensionDevelopmentLocationURI: this._environmentService.extensionDevelopmentLocationURI,