Yes, to use Easy Comments-GPT you will need a ChatGPT API key. When configuring the extension for the first time, you will be prompted to enter your API key. This key will allow the extension to communicate directly with ChatGPT and generate personalized comments based on your preferences. If you don't already have an API key, you can get one from OpenAI. Once you have your key in hand, all you have to do is enter it into the settings of Easy Comments-GPT, and you will be good to go.