diff --git a/src/vs/workbench/api/common/extHost.protocol.ts b/src/vs/workbench/api/common/extHost.protocol.ts
index 4eefe4737b6..22f06f004e6 100644
--- a/src/vs/workbench/api/common/extHost.protocol.ts
+++ b/src/vs/workbench/api/common/extHost.protocol.ts
@@ -679,7 +679,7 @@ export interface MainThreadDebugServiceShape extends IDisposable {
 	$acceptDAExit(handle: number, code: number | undefined, signal: string | undefined): void;
 	$registerDebugConfigurationProvider(type: string, hasProvideMethod: boolean, hasResolveMethod: boolean, hasProvideDaMethod: boolean, handle: number): Promise<void>;
 	$registerDebugAdapterDescriptorFactory(type: string, handle: number): Promise<void>;
-	$registerDebugAdapterTrackerFactory(type: string, handle: number);
+	$registerDebugAdapterTrackerFactory(type: string, handle: number): Promise<any>;
 	$unregisterDebugConfigurationProvider(handle: number): void;
 	$unregisterDebugAdapterDescriptorFactory(handle: number): void;
 	$unregisterDebugAdapterTrackerFactory(handle: number): void;
diff --git a/src/vs/workbench/api/node/extHost.api.impl.ts b/src/vs/workbench/api/node/extHost.api.impl.ts
index 629e7c38ba0..01864265c94 100644
--- a/src/vs/workbench/api/node/extHost.api.impl.ts
+++ b/src/vs/workbench/api/node/extHost.api.impl.ts
@@ -431,13 +431,13 @@ export function createApiFactory(
 			onDidChangeWindowState(listener, thisArg?, disposables?) {
 				return extHostWindow.onDidChangeWindowState(listener, thisArg, disposables);
 			},
-			showInformationMessage(message, first, ...rest) {
+			showInformationMessage(message: string, first: vscode.MessageOptions | string | vscode.MessageItem, ...rest: Array<string | vscode.MessageItem>) {
 				return extHostMessageService.showMessage(extension, Severity.Info, message, first, rest);
 			},
-			showWarningMessage(message, first, ...rest) {
+			showWarningMessage(message: string, first: vscode.MessageOptions | string | vscode.MessageItem, ...rest: Array<string | vscode.MessageItem>) {
 				return extHostMessageService.showMessage(extension, Severity.Warning, message, first, rest);
 			},
-			showErrorMessage(message, first, ...rest) {
+			showErrorMessage(message: string, first: vscode.MessageOptions | string | vscode.MessageItem, ...rest: Array<string | vscode.MessageItem>) {
 				return extHostMessageService.showMessage(extension, Severity.Error, message, first, rest);
 			},
 			showQuickPick(items: any, options: vscode.QuickPickOptions, token?: vscode.CancellationToken): any {
@@ -538,17 +538,17 @@ export function createApiFactory(
 			findFiles: (include, exclude, maxResults?, token?) => {
 				return extHostWorkspace.findFiles(typeConverters.GlobPattern.from(include), typeConverters.GlobPattern.from(withNullAsUndefined(exclude)), maxResults, extension.identifier, token);
 			},
-			findTextInFiles: (query: vscode.TextSearchQuery, optionsOrCallback, callbackOrToken?, token?: vscode.CancellationToken) => {
+			findTextInFiles: (query: vscode.TextSearchQuery, optionsOrCallback: vscode.FindTextInFilesOptions | ((result: vscode.TextSearchResult) => void), callbackOrToken?: vscode.CancellationToken | ((result: vscode.TextSearchResult) => void), token?: vscode.CancellationToken) => {
 				let options: vscode.FindTextInFilesOptions;
 				let callback: (result: vscode.TextSearchResult) => void;
 
 				if (typeof optionsOrCallback === 'object') {
 					options = optionsOrCallback;
-					callback = callbackOrToken;
+					callback = callbackOrToken as (result: vscode.TextSearchResult) => void;
 				} else {
 					options = {};
 					callback = optionsOrCallback;
-					token = callbackOrToken;
+					token = callbackOrToken as vscode.CancellationToken;
 				}
 
 				return extHostWorkspace.findTextInFiles(query, options || {}, callback, extension.identifier, token);
diff --git a/src/vs/workbench/api/node/extHostConfiguration.ts b/src/vs/workbench/api/node/extHostConfiguration.ts
index 985d2407736..c68dc36a39b 100644
--- a/src/vs/workbench/api/node/extHostConfiguration.ts
+++ b/src/vs/workbench/api/node/extHostConfiguration.ts
@@ -125,7 +125,7 @@ export class ExtHostConfigProvider {
 				if (typeof result === 'undefined') {
 					result = defaultValue;
 				} else {
-					let clonedConfig = undefined;
+					let clonedConfig: any | undefined = undefined;
 					const cloneOnWriteProxy = (target: any, accessor: string): any => {
 						let clonedTarget: any | undefined = undefined;
 						const cloneTarget = () => {
@@ -209,7 +209,7 @@ export class ExtHostConfigProvider {
 	}
 
 	private _toReadonlyValue(result: any): any {
-		const readonlyProxy = (target) => {
+		const readonlyProxy = (target: any): any => {
 			return isObject(target) ?
 				new Proxy(target, {
 					get: (target: any, property: string) => readonlyProxy(target[property]),
diff --git a/src/vs/workbench/api/node/extHostMessageService.ts b/src/vs/workbench/api/node/extHostMessageService.ts
index bede16ea336..e3efdde6f21 100644
--- a/src/vs/workbench/api/node/extHostMessageService.ts
+++ b/src/vs/workbench/api/node/extHostMessageService.ts
@@ -22,7 +22,8 @@ export class ExtHostMessageService {
 
 	showMessage(extension: IExtensionDescription, severity: Severity, message: string, optionsOrFirstItem: vscode.MessageOptions | string, rest: string[]): Promise<string | undefined>;
 	showMessage(extension: IExtensionDescription, severity: Severity, message: string, optionsOrFirstItem: vscode.MessageOptions | vscode.MessageItem, rest: vscode.MessageItem[]): Promise<vscode.MessageItem | undefined>;
-	showMessage(extension: IExtensionDescription, severity: Severity, message: string, optionsOrFirstItem: vscode.MessageOptions | string | vscode.MessageItem, rest: (string | vscode.MessageItem)[]): Promise<string | vscode.MessageItem | undefined> {
+	showMessage(extension: IExtensionDescription, severity: Severity, message: string, optionsOrFirstItem: vscode.MessageOptions | vscode.MessageItem | string, rest: Array<vscode.MessageItem | string>): Promise<string | vscode.MessageItem | undefined>;
+	showMessage(extension: IExtensionDescription, severity: Severity, message: string, optionsOrFirstItem: vscode.MessageOptions | string | vscode.MessageItem, rest: Array<string | vscode.MessageItem>): Promise<string | vscode.MessageItem | undefined> {
 
 		const options: MainThreadMessageOptions = { extension };
 		let items: (string | vscode.MessageItem)[];
diff --git a/src/vs/workbench/api/node/extHostTypes.ts b/src/vs/workbench/api/node/extHostTypes.ts
index f875655a334..756d945c972 100644
--- a/src/vs/workbench/api/node/extHostTypes.ts
+++ b/src/vs/workbench/api/node/extHostTypes.ts
@@ -1058,15 +1058,15 @@ export class CodeAction {
 export class CodeActionKind {
 	private static readonly sep = '.';
 
-	public static Empty;
-	public static QuickFix;
-	public static Refactor;
-	public static RefactorExtract;
-	public static RefactorInline;
-	public static RefactorRewrite;
-	public static Source;
-	public static SourceOrganizeImports;
-	public static SourceFixAll;
+	public static Empty: CodeActionKind;
+	public static QuickFix: CodeActionKind;
+	public static Refactor: CodeActionKind;
+	public static RefactorExtract: CodeActionKind;
+	public static RefactorInline: CodeActionKind;
+	public static RefactorRewrite: CodeActionKind;
+	public static Source: CodeActionKind;
+	public static SourceOrganizeImports: CodeActionKind;
+	public static SourceFixAll: CodeActionKind;
 
 	constructor(
 		public readonly value: string