This script can spy on changes of a webpage content. When the page is changed as expected, user will be notified by the text message.
NOTE: It uses a thirdparty service named tui3 for sending message. You can apply for it on the website and acquire the API key.
In the configuration file, user can assign the keyword that need to be focused.
Adding the work to Cron job is a feasible way if the webpage needs to be checked continuously.