diff --git a/script/tei2korapxml b/script/tei2korapxml
index ed6b488..09f2a81 100755
--- a/script/tei2korapxml
+++ b/script/tei2korapxml
@@ -38,6 +38,8 @@
 
 our $VERSION_MSG = "\ntei2korapxml - v$VERSION\n";
 
+# Set to 1 for minimal more debug output (no need to be parametrized)
+use constant DEBUG => $ENV{KORAPXMLTEI_DEBUG} // 0;
 
 # Parse options from the command line
 GetOptions(
@@ -66,6 +68,8 @@
 
 Log::Any::Adapter->set('Stderr', log_level => $log_level);
 
+$log->notice('Debugging is activated') if DEBUG;
+
 #
 # ~~~ parameter (mandatory) ~~~
 #
@@ -108,7 +112,6 @@
 
 my $_tok_dir         = "base";                       # name of directory for storing tokenization files
 
-my $_DEBUG           = 0;                            # set to 1 for minimal more debug output (no need to be parametrized)
 my $_XCT_LN          = 0;                            # only for debugging: include line numbers in elements of $tree_data
                                                      #  (see also manpage of XML::CompactTree::XS)
 
@@ -286,7 +289,7 @@
           # ~ recursion ~
           retr_info(1, \$tree_data->[2] ); # parse input data
 
-          if ($_DEBUG) {
+          if (DEBUG) {
             $log->debug("Writing (utf8-formatted) xml file $dir/$_data_file");
           };
 
@@ -423,7 +426,7 @@
       # Write header to zip
       my $file = $header->dir . '/' . $_header_file;
 
-      $log->debug("Writing file $file") if $_DEBUG;
+      $log->debug("Writing file $file") if DEBUG;
 
       $header->to_zip($zipper->new_stream($file));
 
@@ -868,6 +871,22 @@
 
 =back
 
+=head1 ENVIRONMENT VARIABLES
+
+=over 2
+
+=item B<KORAPXMLTEI_DEBUG>
+
+Activate minimal debugging.
+Defaults to C<false>.
+
+=item B<KORAPXMLTEI_INLINE>
+
+Process inline annotations, if present.
+Defaults to C<false>.
+
+=back
+
 =head1 COPYRIGHT AND LICENSE
 
 Copyright (C) 2020, L<IDS Mannheim|https://www.ids-mannheim.de/>