Grammarly revolves around AI-based writing suggestions, but now it's giving you an at-a-glance way to see what needs improving. The service's browser and desktop app editors have been updated with color-coded AI suggestions that revolve around four categories. Red underlines point out basic issues of correctness, such as spelling and grammar. Blue addresses clarity problems like concision and difficult-to-read sentence structure, while purple offers advice on the tone of your piece. You'll even see progress bars that show how close you are to refining your writing in a given category.