diff --git a/src/cc/dapps/zmigrate.c b/src/cc/dapps/zmigrate.c
index 276815363..643a16ca2 100644
--- a/src/cc/dapps/zmigrate.c
+++ b/src/cc/dapps/zmigrate.c
@@ -19,6 +19,20 @@
 #include <memory.h>
 #include "cJSON.c"
 
+/*
+z_migrate: the purpose of z_migrate is to make converting of all sprout outputs into sapling. the usage would be for the user to specify a sapling address and call z_migrate zsaddr, until it returns that there is nothing left to be done.
+
+its main functionality is quite similar to a z_mergetoaddress ANY_ZADDR -> onetime_taddr followed by a z_sendmany onetime_taddr -> zsaddr
+
+since the z_mergetoaddress will take time, it would just queue up an async operation. When it starts, it should see if there are any onetime_taddr with 10000.0001 funds in it, that is a signal for it to do the sapling tx and it can just do that without async as it is fast enough, especially with a taddr input. Maybe it limits itself to one,  or it does all possible taddr -> sapling as fast as it can. either is fine as it will be called over and over anyway.
+
+It might be that there is nothing to do, but some operations are pending. in that case it would return such a status. as soon as the operation finishes, there would be more work to do.
+
+the amount sent to the taddr, should be 10000.0001
+
+The GUI or user would be expected to generate a sapling address and then call z_migrate saplingaddr in a loop, until it returns that it is all done. this loop should pause for 10 seconds or so, if z_migrate is just waiting for opid to complete.
+*/
+
 bits256 zeroid;
 
 char hexbyte(int32_t c)