diff -r c7b73000a1ed -r 4d8a55a7618b src/server/proxy/httpclient.h
--- a/src/server/proxy/httpclient.h	Sat Feb 21 11:17:37 2026 +0100
+++ b/src/server/proxy/httpclient.h	Sat Feb 21 13:12:39 2026 +0100
@@ -91,6 +91,9 @@
      * Response start callback function
      * 
      * int response_start(HttpClient *client, int status, char *message, void *userdata)
+     * 
+     * Return: 0 success
+     *         HTTP_CLIENT_CALLBACK_WOULD_BLOCK or HTTP_CLIENT_CALLBACK_ERROR
      */
     int (*response_start)(HttpClient *, int, char *, void *);
     void *response_start_userdata;
@@ -129,6 +132,7 @@
     
     size_t req_contentlength_pos;
     
+    int stage; // 0: request, 1: response
     int request_body_complete;
     int request_body_terminated;
     int response_header_complete;