- A Princeton student built an app that aims to tell if essays were written by AIs like ChatGPT.—Edward Tian (@edward_the6) January 3, 2023GPTZero scores text on its "perplexity and burstiness" – referring to how complicated it is and how randomly it is written.GPTZero is still available to use on Tian's Streamlit page, after the website hosts stepped in to increase its capacity.Tian, a former data journalist with the BBC, said that he was motivated to build GPTZero after seeing increased instances of AI plagiarism.Insider's Beatrice Nolan also tested ChatGPT to write cover letters for job applications, with one hiring manager saying she'd have got an interview, though another said the letter lacked personality."