yanglint DOC unify help text for --operational
diff --git a/tools/lint/main_ni.c b/tools/lint/main_ni.c
index 3987e08..7b25e45 100644
--- a/tools/lint/main_ni.c
+++ b/tools/lint/main_ni.c
@@ -153,7 +153,8 @@
" printing them in the specified format.\n\n"
" yanglint -t (nc-)rpc/notif [-O <operational-file>] <schema>... <file>\n"
" Validates the YANG/NETCONF RPC/notification <file> according to the <schema>(s) using\n"
- " <operational-file> with possible references to the operational datastore data.\n\n"
+ " <operational-file> with possible references to the operational datastore data.\n"
+ " To validate nested-notification or action, the <operational-file> is required.\n\n"
" yanglint -t nc-reply -R <rpc-file> [-O <operational-file>] <schema>... <file>\n"
" Validates the NETCONF rpc-reply <file> of RPC <rpc-file> according to the <schema>(s)\n"
" using <operational-file> with possible references to the operational datastore data.\n\n"
@@ -282,8 +283,8 @@
" Provide optional data to extend validation of the '(nc-)rpc',\n"
" '(nc-)reply' or '(nc-)notif' TYPEs. The FILE is supposed to contain\n"
" the operational datastore referenced from the operation.\n"
- " In case of a nested operation, its parent existence is also\n"
- " checked in these operational data.\n\n");
+ " In case of a nested notification or action, its parent existence\n"
+ " is also checked in these operational data.\n\n");
printf(" -R FILE, --reply-rpc=FILE\n"
" Provide source RPC for parsing of the 'nc-reply' TYPE. The FILE\n"