It's a crossword with no clues, just a grid with a few pre-filled letters to get you started. You deduce the words from the letter intersections alone. Like Wordle, there's one set of puzzles per day (resets at midnight local time).
The goal is simple: complete the grid in as little time as possible, using as few hints as you can. Then share your score with friends. If the first puzzle is too easy, you can attempt a harder "master" version of it.
The entire thing is self-contained, so feel free to save the page and host it elsewhere if you want to guarantee long-term playability.