It is an AI-powered email builder called Potion. It discusses that Potion is a Notion-style email builder with AI-powered autocompletion. The article also mentions that there is no signup or credit card required to get started. Let me know if you would like to learn more about Potion or if you have other questions!

Potion, a Notion-style email builder with AI-powered autocompletion summarized from the webpage. It discusses how to get started with Potion for free without any signup or credit card. Potion's output is tested on popular email clients.