--- a/doc/Low-level-commands	Wed Feb 17 19:04:00 2021 +0000
+++ b/doc/Low-level-commands	Wed Feb 17 19:18:20 2021 +0000
@@ -70,7 +70,16 @@
 practice, as the SIM will normally reject any requested length that does not
 match the current EF record length.
 
-readef
+readef File_ID
+
+This fc-simtool command provides a slightly higher-level facility for examining
+the content of transparent EFs, combining select and readbin operations.  The
+sole File_ID argument is the same as for the low-level select command; if the
+SIM response to this SELECT indicates a transparent EF (it is an error
+otherwise), readef follows up with a READ BINARY command to read the entire file
+(or the first 256 bytes if the file is longer) and displays the read content in
+raw hex.
+
 savebin
 
 Writing commands