I spend a lot of time on design before I start coding. I started designing as soon as I heard about the jam. I had this really interesting idea, but couldn't work out how to make it into a game, so I started writing up lists of things related to Christmas. To cut a long story short, I've now come up with something completely different to my original idea. I've drawn a map, populated it with objects and characters, worked out the story and the objective and lots of intertwined puzzles.
A significant part of the game requires the player to gather information from characters and elsewhere. I'm working on this aspect now. I hope this works smoothly in practice. There will be plenty of in-game hints, but it does require multi-word input.
I've been prototyping this in Inform 6 and the game plays well, so far. I'm hoping to finish the prototype in a week, then I'll port it to Adventuron. Graphics are my weak spot, so I need to allow plenty of time for that.