You have to select the part of the text, and click on the "convert" button. Does the work, but too simple for me. For instance, when I select an image, it gives me a warning asking for the URL of the image. There's no option to fix the warning by adding variables, as images URL. So, it's a good tool, as it's very simple and convert some format into markdown, but no complex things (or I don't know how to use it effectively). The fact it's simple is also an avantage, as convert effectively docs containing lists and tables into markdown. But I prefer "Docs to Markdown", it gives HTML and Markdown, and keeps more formatting.