diff --git a/doc/cli-design.txt b/doc/cli-design.txt
index 24bbece..88b62a9 100644
--- a/doc/cli-design.txt
+++ b/doc/cli-design.txt
@@ -2,7 +2,7 @@ A flexible music programming language powered by math.
 
 usage:
 
-blip [play [FILENAME | -c SHEET_MUSIC] [-e EXPR] [-l EXPR] -n NOTE[,...] [-v CHAR=VALUE] | export [FILENAME | -c SHEET_MUSIC] [-e EXPR] [-l EXPR] -n NOTE[,...] [-v CHAR=VALUE] [-f FORMAT] [-o FILENAME] | help [syntax | examples | example <n> | formats]]
+blip [play [FILENAME | -c SHEET_MUSIC] [-i EXPR] [-l EXPR] -n NOTE[,...] [-v CHAR=VALUE] | export [FILENAME | -c SHEET_MUSIC] [-i EXPR] [-l EXPR] -n NOTE[,...] [-v CHAR=VALUE] [-f FORMAT] [-o FILENAME] | help [syntax | examples | example <n> | formats]]
 
 
 modes:
@@ -13,7 +13,7 @@ modes:
             sheet music to read instead of reading a file
         -n NOTE[,...], --notes NOTE[,...]
             available notes: a list of comma-separated alphabetical note names
-        -e EXPR, --expression EXPR
+        -i EXPR, --instrument EXPR
             signal expression (instrument) to generate music samples (you can use the floating-point number t for the current time in seconds, n for the indice of the currently playing note in the list of available notes starting with 0 and N for the number of available notes)  [default: "sin(2*PI*(442+442*((n+1)/N))*t)"]
         -l EXPR, --length EXPR
             expression to generate note length in seconds  [default: "2^(2-log_2(l))*(60/T)"]
@@ -31,7 +31,7 @@ modes:
             sheet music to read instead of reading a file
         -n NOTE[,...], --notes NOTE[,...]
             available notes: a list of comma-separated alphabetical note names
-        -e EXPR, --expression EXPR
+        -i EXPR, --instrument EXPR
             signal expression (instrument) to generate music samples (you can use the floating-point number t for the current time in seconds, n for the indice of the currently playing note in the list of available notes starting with 0 and N for the number of available notes)  [default: "sin(2*PI*(442+442*((n+1)/N))*t)"]
         -l EXPR, --length EXPR
             expression to generate note length in seconds  [default: "2^(2-log_2(l))*(60/T)"]
@@ -46,7 +46,7 @@ modes:
             see "help formats"
         -o, --output FILENAME
             output file [default: standard out]
-            
+
     help - help menu
         syntax
             show a help message about expression and sheet music syntax