diff --git a/code/common/packets/packet_utils.h b/code/common/packets/packet_utils.h
index 7a92f4d..bdf0374 100644
--- a/code/common/packets/packet_utils.h
+++ b/code/common/packets/packet_utils.h
@@ -99,4 +99,10 @@ inline int32_t pkt_msg_decode(pkt_header *header, pkt_desc* desc, uint32_t args,
     PKT_IF(pkt_unpack_struct(&uc, desc, raw_blob, blob_size));
     
     return pkt_validate_eof_msg(&uc);
-}
\ No newline at end of file
+}
+
+inline size_t pkt_pack_desc_args(pkt_desc *desc) {
+    size_t cnt = 0;
+    for (pkt_desc *field = desc; field->type != CWP_NOT_AN_ITEM; ++field, ++cnt) {}
+    return cnt;
+}
diff --git a/code/common/packets/pkt_01_welcome.c b/code/common/packets/pkt_01_welcome.c
index a3e474d..bff09cc 100644
--- a/code/common/packets/pkt_01_welcome.c
+++ b/code/common/packets/pkt_01_welcome.c
@@ -1,9 +1,8 @@
 #include "pkt_01_welcome.h"
+#include "packet_utils.h"
 #include "world.h"
 #include "game.h"
 
-#define PKT_01_WELCOME_ARGC 3
-
 pkt_desc pkt_01_welcome_desc[] = {
     { PKT_FIELD(CWP_ITEM_POSITIVE_INTEGER, pkt_01_welcome, block_size) },
     { PKT_FIELD(CWP_ITEM_POSITIVE_INTEGER, pkt_01_welcome, chunk_size) },
@@ -13,14 +12,14 @@ pkt_desc pkt_01_welcome_desc[] = {
 
 size_t pkt_01_welcome_encode(pkt_01_welcome *table) {
     cw_pack_context pc = {0};
-    pkt_pack_msg(&pc, PKT_01_WELCOME_ARGC);
+    pkt_pack_msg(&pc, pkt_pack_desc_args(pkt_01_welcome_desc));
     pkt_pack_struct(&pc, pkt_01_welcome_desc, PKT_STRUCT_PTR(table));
     return pkt_pack_msg_size(&pc);
 }
 
 int32_t pkt_01_welcome_handler(pkt_header *header) {
     pkt_01_welcome table;
-    PKT_IF(pkt_msg_decode(header, pkt_01_welcome_desc, PKT_01_WELCOME_ARGC, PKT_STRUCT_PTR(&table)));
+    PKT_IF(pkt_msg_decode(header, pkt_01_welcome_desc, pkt_pack_desc_args(pkt_01_welcome_desc), PKT_STRUCT_PTR(&table)));
 
     zpl_printf("we received: block_size: %d, chunk_size: %d and world_size: %d\n", table.block_size, table.chunk_size, table.world_size);