diff --git a/src/index.ts b/src/index.ts
index 6cbf7d1..b56b152 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -43,7 +43,7 @@ export {
 // HttpClient2 is keep compatible with urllib@2 HttpClient2
 export {
   HttpClient, HttpClient as HttpClient2, HEADER_USER_AGENT as USER_AGENT,
-  RequestDiagnosticsMessage, ResponseDiagnosticsMessage,
+  RequestDiagnosticsMessage, ResponseDiagnosticsMessage, ClientOptions,
 } from './HttpClient.js';
 // RequestOptions2 is keep compatible with urllib@2 RequestOptions2
 export {
@@ -51,6 +51,8 @@ export {
   FixJSONCtlCharsHandler, FixJSONCtlChars,
 } from './Request.js';
 
+export { CheckAddressFunction } from './HttpAgent.js';
+
 export {
   SocketInfo, Timing, RawResponseWithMeta, HttpClientResponse,
 } from './Response.js';