If you would like to shorten a URL by having TextExpander on macOS grab the URL from your clipboard and replace it with your personal YOURLS shortener using a TE snippet, here you go:

Copy your signature token from the Admin Tools page in your install of YOURLS.

In TextExpander create a shell script snippet by clicking on the Content drop down menu at the top where it says Plain Text, and choose Shell Script.

Add the following script for the body of the snippet, replacing the necessary parts with your own information of course.

curl --silent -o - "http://YOURLS_URL_HERE/yourls-api.php?signature=$id&action=shorturl&format=simply&url=%clipboard" |
awk -F# '{gsub(/ /,"");print ($1) }'

Then add your label and abbreviation. You are all set.