This employee directory application uses Ruby on Rails and Twilio to allow users to query for employee information by sending an SMS with the employee's name to a designated Twilio number. The application handles three possible scenarios: finding an exact match, a single partial match, and multiple partial matches. In each scenario, it sends a TwiML response back to Twilio, which then sends an SMS message to the user containing the relevant information or suggestions for further action. The application also uses Twilio Cookies to store search suggestions in the browser's cookies, allowing users to build on previous searches and providing a more seamless experience.