NadekoBot/docs/customreactions.md

After you add/delete custom commands, you should restart the bot. (either by typing .restart if you are on WINDOWS or just manually restarting if you prefer/are on other platform)

.acr and .dcr require you to be a bot owner.

.acr Adds a new custom command. If you add multiple commands with the same name, it will pick random one. First argument is the name, second one is the response. For example .acr hello hi. Now the bot will reply hi whenever someone types hello. For more than 1 word command, wrap it in ". For example: .acr "hello there" hi there - now it will print "hi there" whenever someone types "hello there". Currently you can add this placeholders which will get replaced with appropriate text:
%mention% - replaces it with bot mention
%user% - replaces it with the user runner's mention
%target% - replaces it with a mention of another person from within the original message
%rng% replaces it with a random number
for example: .acr "%mention% hello" Hello %user%
(we will add much more of these over time)

.dcr "command name" (optional index) Deletes either whole custom command and all its responses or a single command's response via an index (if you have multiple responses for the same command). For example: .dcr "hi there" or .dcr "hi there" 1. You can get an index by using .lcr [page number]

.lcr [number] Prints a list of custom reactions. Paginated. (for example: .lcr 1 or .lcr 4)