Some of you probably have a pretty good idea of how you will build your game while others may still be deciding. Here I'll list a few tools specifically for making adventure games.
Adventure Creator
If you are a Unity developer and you make adventure games, do yourself a favor and get Adventure Creator. Even the programming inept can make an adventure game using this tool, but if you are a programmer, it allows for custom additions to its already quite extensive base functionality. Because it's a plugin to Unity, there are no bounds to what can be accomplished. This tool has been used to make a significant number of recent commercial adventure games such as Bear With Me and Duke Grabowski. You can pick it up for $70 on the Unity Asset Store. https://www.adventurecreator.org/
Adventure Game Studio
I don't think it's too much to say that this tool was one of the driving forces keeping adventure games alive during the dark years. When big game studios wouldn't touch the genre with a ten foot pole, AGS has sported a thriving community of independent adventure game developers since 1997 and is still going strong today because of its power and flexibility. Many commercial adventure game studios use this tool, most notably Wadjet Eye Games. It is free to use and can be downloaded from its web site. http://www.adventuregamestudio.co.uk/
Visionaire Studio
I have not used this tool so I can't say much about it. If you have more info on this, feel free to chime in. It appears to cost about $60 and the web page is here https://www.visionaire-studio.net/
Adventure Game Engine
I have not used this tool so I can't say much about it. If you have more info on this, feel free to chime in. It is free to use and can be downloaded from its site http://age.seccia.com/
Wintermute
I have not used this tool so I can't say much about it. If you have more info on this, feel free to chime in. It's free but doesn't seem to have been updated since 2010. The website is here http://dead-code.org
Others?
Do you know of any other adventure game creation tools that should be on this list? Do you have more info on the ones I haven't used? Reply below!