diff --git a/src/vs/vscode.d.ts b/src/vs/vscode.d.ts
index 7493f91c0b5..f99b914fa7e 100644
--- a/src/vs/vscode.d.ts
+++ b/src/vs/vscode.d.ts
@@ -3164,7 +3164,7 @@ declare module 'vscode' {
 		 */
 		public readonly tokenModifiers: string[];
 
-		constructor(tokenTypes: string[], tokenModifiers: string[]);
+		constructor(tokenTypes: string[], tokenModifiers?: string[]);
 	}
 
 	/**
@@ -3184,7 +3184,7 @@ declare module 'vscode' {
 		 * @param tokenType The encoded token type.
 		 * @param tokenModifiers The encoded token modifiers.
 		 */
-		push(line: number, char: number, length: number, tokenType: number, tokenModifiers: number): void;
+		push(line: number, char: number, length: number, tokenType: number, tokenModifiers?: number): void;
 
 		/**
 		 * Add another token. Use only when providing a legend.
diff --git a/src/vs/workbench/api/common/extHostTypes.ts b/src/vs/workbench/api/common/extHostTypes.ts
index 5b14380f8aa..f57d386ee87 100644
--- a/src/vs/workbench/api/common/extHostTypes.ts
+++ b/src/vs/workbench/api/common/extHostTypes.ts
@@ -2420,7 +2420,7 @@ export class SemanticTokensLegend {
 	public readonly tokenTypes: string[];
 	public readonly tokenModifiers: string[];
 
-	constructor(tokenTypes: string[], tokenModifiers: string[]) {
+	constructor(tokenTypes: string[], tokenModifiers: string[] = []) {
 		this.tokenTypes = tokenTypes;
 		this.tokenModifiers = tokenModifiers;
 	}
@@ -2461,10 +2461,13 @@ export class SemanticTokensBuilder {
 		}
 	}
 
-	public push(line: number, char: number, length: number, tokenType: number, tokenModifiers: number): void;
+	public push(line: number, char: number, length: number, tokenType: number, tokenModifiers?: number): void;
 	public push(range: Range, tokenType: string, tokenModifiers?: string[]): void;
 	public push(arg0: any, arg1: any, arg2: any, arg3?: any, arg4?: any): void {
-		if (typeof arg0 === 'number' && typeof arg1 === 'number' && typeof arg2 === 'number' && typeof arg3 === 'number' && typeof arg4 === 'number') {
+		if (typeof arg0 === 'number' && typeof arg1 === 'number' && typeof arg2 === 'number' && typeof arg3 === 'number' && (typeof arg4 === 'number' || typeof arg4 === 'undefined')) {
+			if (typeof arg4 === 'undefined') {
+				arg4 = 0;
+			}
 			// 1st overload
 			return this._pushEncoded(arg0, arg1, arg2, arg3, arg4);
 		}
diff --git a/src/vs/workbench/test/browser/api/extHostTypes.test.ts b/src/vs/workbench/test/browser/api/extHostTypes.test.ts
index ea4abb68958..92e9616c1a8 100644
--- a/src/vs/workbench/test/browser/api/extHostTypes.test.ts
+++ b/src/vs/workbench/test/browser/api/extHostTypes.test.ts
@@ -587,6 +587,18 @@ suite('ExtHostTypes', function () {
 		]);
 	});
 
+	test('SemanticTokensBuilder no modifier', () => {
+		const builder = new types.SemanticTokensBuilder();
+		builder.push(1, 0, 5, 1);
+		builder.push(1, 10, 4, 2);
+		builder.push(2, 2, 3, 2);
+		assert.deepEqual(toArr(builder.build().data), [
+			1, 0, 5, 1, 0,
+			0, 10, 4, 2, 0,
+			1, 2, 3, 2, 0
+		]);
+	});
+
 	test('SemanticTokensBuilder out of order 1', () => {
 		const builder = new types.SemanticTokensBuilder();
 		builder.push(2, 0, 5, 1, 1);