the description could mention that it does not matter whether our path is open or closed (a closed tour is one in which the knight can reach the starting position from the final position)

Fun kata, thank you. I was able to solve this as a particular case of a more general problem.

A couple of suggestions to improve the description:

• explain that the coordinates range from 0 to n - 1 (typically, in chess, rows and columns range from 1 to n);
• at least for Python, the expected result is a list of tuples, not a "2D array".