diff --git a/libmctp.h b/libmctp.h
index a8beb72..00bce29 100644
--- a/libmctp.h
+++ b/libmctp.h
@@ -65,6 +65,7 @@
 struct mctp_bus;
 
 struct mctp *mctp_init(void);
+void mctp_set_max_message_size(struct mctp *mctp, size_t message_size);
 void mctp_destroy(struct mctp *mctp);
 
 /* Register a binding to the MCTP core, and creates a bus (populating