I am working on a template for constructing my Game Design Document with Editorial.
I have a few Workflows already, that will help make it easier (search "Doctor").
For anyone that has an iPad, I think this is a good way to create any sort of document. I can even convert it to LaTex if I wanted.
I found a really nice example of a game design document:
http://marceltau.com/files/Arcana_Project_GDD.pdf
It's a nice document, as a programmer I would love to work having something like this.
But I have some issues:
1) Such level of detail in GDD guarantees there won't be anything unique or original in such game, it will be bland and overused. I mean, if you go fo original it MUST be messy and you can't plan everything, it has to be discovered not written down upfront.
2) They ignored prototype, they didn't have any plans to redesign the game based on the feedback they get from testers/players after releasing the prototype (which frequently results in a mediocre game).
3) This GDD completely lacks the promotional texts. That's the first thing I write down, how I will advertise the game, and then I tend to REDESIGN the game to fit this fun description. It's extremelly crucial and it will benefit the game.
4) That game is pretty simple, and honestly, you don't need any GDD to write something like this in the first place :) They could have just written down "let's make a game like XXX except [put a feature here]", yet again, it has some uses. If you go for unoriginal mass produced casual games that GDD is perfect to send to your programmers, they will love you for it :)
It's your first game. Forget about all this, it does not matter, it's irrelevant, it only distracts you, it will make you fail. Make a clone of some game you like (and maybe improve it, but only after you got the core gameplay working). Believe me, with your first game it will be hard enough without all this originality thing. You are not at the level to worry about "GDD automator" (whatever it means :)), worry about simplier, much simplier things. Save all this for your second game.
So in summary:
I could amlost make a private GDD automator (template at least)
A GDD for a someone who is working alone is really just a place to work on the project and organize your tasks for when you can't dedicate to the tasks themselves. I don't see one format of GDD suiting everyone.
Think of all the assets you're going to need and where to get them. What challenges or dilemmas could you face when you're creating your AI, pathfinding or inventory for example. I believe every game developer asks themselves these questions sooner or later. Hard things can prove quite easy when you lift it on the table and start writing things down. Or vice versa. A GDD is nevertheless a place where you can start answering your questions and regard yourself better prepared than prior to writing it :)
In team projects it has more important job of communicating between members, things have much more strict schedule and priority order so that every member can progress fluently and purposefully within their field without having to wait other assets that haven't been finished or designed yet. In commercial projects it also links to the bureaucracy and budget: how the spent and spare resources are in balance compared to the budget and schedule.
Also a pointer about the detail level: it doesn't matter but don't plan too much ahead. There's no use designing every number and feature in detail before you've done rudimentary playtesting to see if the concept will fly at all. Expand on "width" axis meaning it's better to design 7 enemies on crude level (and scrap 3 of them later if they don't work out at all) than trying to polish 2 enemies in detail before you have anything playable.
TL; DR: It's for you, make it as it suits you, but understand what it's for :)
