diff --git a/src/hush_bitcoind.h b/src/hush_bitcoind.h
index 58428d75c..e44c1eb6d 100644
--- a/src/hush_bitcoind.h
+++ b/src/hush_bitcoind.h
@@ -724,6 +724,7 @@ int32_t hush_block2height(CBlock *block)
     return(height);
 }
 
+// return true if the first output of the first tx in a block is valid
 int32_t hush_block2pubkey33(uint8_t *pubkey33,CBlock *block)
 {
     int32_t n;