diff --git a/src/vs/workbench/api/common/extHost.api.impl.ts b/src/vs/workbench/api/common/extHost.api.impl.ts
index 23ef3d71187..d3c6638851a 100644
--- a/src/vs/workbench/api/common/extHost.api.impl.ts
+++ b/src/vs/workbench/api/common/extHost.api.impl.ts
@@ -1438,8 +1438,10 @@ export function createApiFactoryAndRegisterActors(accessor: ServicesAccessor): I
 				checkProposedApiEnabled(extension, 'languageModels');
 				return extHostLanguageModels.onDidChangeProviders(listener, thisArgs, disposables);
 			},
-			sendChatRequest(languageModel: string, messages: (vscode.LanguageModelChatMessage | vscode.LanguageModelChatMessage2)[], options: vscode.LanguageModelChatRequestOptions, token: vscode.CancellationToken) {
+			sendChatRequest(languageModel: string, messages: (vscode.LanguageModelChatMessage | vscode.LanguageModelChatMessage2)[], options?: vscode.LanguageModelChatRequestOptions, token?: vscode.CancellationToken) {
 				checkProposedApiEnabled(extension, 'languageModels');
+				token ??= CancellationToken.None;
+				options ??= {};
 				return extHostLanguageModels.sendChatRequest(extension, languageModel, messages, options, token);
 			},
 			computeTokenLength(languageModel: string, text: string | vscode.LanguageModelChatMessage, token?: vscode.CancellationToken) {
diff --git a/src/vscode-dts/vscode.proposed.languageModels.d.ts b/src/vscode-dts/vscode.proposed.languageModels.d.ts
index 8e56ee576f5..a54e68a5106 100644
--- a/src/vscode-dts/vscode.proposed.languageModels.d.ts
+++ b/src/vscode-dts/vscode.proposed.languageModels.d.ts
@@ -316,7 +316,7 @@ declare module 'vscode' {
 		 * @param token A cancellation token which controls the request. See {@link CancellationTokenSource} for how to create one.
 		 * @returns A thenable that resolves to a {@link LanguageModelChatResponse}. The promise will reject when the request couldn't be made.
 		 */
-		export function sendChatRequest(languageModel: string, messages: (LanguageModelChatMessage | LanguageModelChatMessage2)[], options: LanguageModelChatRequestOptions, token: CancellationToken): Thenable<LanguageModelChatResponse>;
+		export function sendChatRequest(languageModel: string, messages: (LanguageModelChatMessage | LanguageModelChatMessage2)[], options?: LanguageModelChatRequestOptions, token?: CancellationToken): Thenable<LanguageModelChatResponse>;
 
 		/**
 		 * Uses the language model specific tokenzier and computes the length in token of a given message.