I used to run into this before too, when I needed to quickly check 2FA without deep code. A site with various useful utilities helped me a lot, including a handy hotp generator there that allows you to generate one-time passwords and check algorithms. I use it to make sure that the system processes the codes correctly and they match. In one project, it made testing a lot easier, because you could quickly compare it with what the server was giving out and not waste time writing your own scripts.