We don't limit ourselves to 5 letter words, and it's really fun when the word is very long. Sometimes it takes a long time to find the word!
A weird issue is finding a list of words that contains every valid French word. It's harder than I thought. I'm not talking about the target words here, but the valid ones that you can use to guess. I thought the 300,000 word list I had found would be good enough, but some pretty basic words such as "Parabolique" are missing. The correct solution would probably be to use a dictionary file instead, instead of a plain list, but I'm not sure there's a python library to parse dictionary files, say the ones from libreoffice.
Also a fun bug was that since I use two completely different lists for the target words and the valid words (the target words list is a list of pretty common French words, it contains ten times fewer words than the valid words list, and it comes from another Internet source), there were words in the target word list but not the valid word list. Due to the order of the checks I do, the target word was deemed incorrect! My friends were certain they had found the correct word, the clues only allowed for one word, but it was rejected again and again. Now I've made sure the target word list is strictly a subset of the bigger list.