A online demo is available at pasteburn.onrender.com. Note that the demo is very unstable and should not be used for purposes other than demonstration. Paste something into pasteburn with a password.
The esp-idf-panic-decoder is a Python-based, open-source package that is part of the ESP-IDF SDK for Espressif products. The main part is a script that parses ESP-IDF panic handler output (registers & ...