Not a hundred-page bible: one page per mechanic, level, and character, each judged against your pillars, kept in the project beside the build. Draw the core loop, keep the reason the double jump was cut, and point every playtest task at the page it changes.
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Sound familiar?
Everyone agrees a game should have a design document. Almost nobody keeps one true.
One long document, read top to bottom once. Past the pillars, people stop, and the page about the mechanic they are building is somewhere on page forty.
Values change in every playtest. Once most of the game is in, the build becomes the reference and the document collects dust.
A doc for the ideas, a sheet for the numbers, a board of stickies for level flow, and notes you texted yourself. Asking a teammate is faster than finding the answer.
How it fits
Every part of the game gets a short page with the same sections each time: why it is in the game, how it should feel, its rules and numbers, and what it will never do. The pages are plain markdown files in your project folder, next to the Godot or Unity project if you like.
What you will use most
Mechanics, levels, and characters as cards that open their pages, joined by labelled arrows, coloured by status as they move from idea to shipped.
“Cut the double jump.” Write the call and the playtest behind it once, confirm it, and it stays on the mechanic’s page for whoever asks next year.
Tasks on a board, each pointing at the mechanic or level it changes, so the page stays the design and the board holds the work.
Images, PDFs, and the balance sheet live in the project and link to the pages they belong to. Rename one and every page follows.
A note from a playtest sits on the rule it is about, signed by whoever wrote it, and closes once the page is updated.
It does nothing until you connect your own agent and ask. If you do, it reads the mechanic’s page before it writes the GDScript or C#, and changes nothing in your design unless you ask.
See the game whole
Lay out what the player spends and what gives it back, with every card a page you can open. Arrows carry labels, frames group a system, and a card’s colour follows its status, so a cut mechanic shows red without anyone repainting the board.
The cut list
A cut mechanic keeps its page, marked Cut, with the decision that cut it: the playtest, what it overlapped, and who confirmed it. When someone suggests the double jump again, the answer is one click away.
Start today
One command sets up the game’s folders, its five framing pages, and the one-pager, cut list, playtest log, and art bible, named in Title Case so the files read like the game’s own pages. Then give your first mechanic a page in the system it belongs to. In the app, pick Game when you start a new project.
$ eidos install @The-Virtual-Panda/game --naming "Title Case"
✓ installed @The-Virtual-Panda/game → Blueprints (Eidos 5.5.0, naming Title Case)
collections: The Game, Mechanics, Levels, Characters, Items
$ eidos new Mechanics "Wall Cling" --group Movement
✓ Mechanics/Movement/Wall Cling.md (Mechanics, mechanic.one-pager, id B-7X1Z)Start here
Game is in the Registry: the game as a whole on five pages, mechanics and items grouped by system, levels by act, and characters, with a page type of their own for enemies. Every page moves from Idea to Shipped, and a cut one keeps its reason. A playtester role sees only what is in the build. If your game is built on its setting, take Places and Factions from World as well.
A video game, a mechanic at a time
Mechanics and items by system, levels by act, characters and enemies, a cut list, a playtest log, and a playtester role that sees only what is in the build.
$ eidos install @The-Virtual-Panda/gameIn the app: New Root, then pick it from the list.
A fictional world, for a series or a table
Places by region, factions, characters, arcs by campaign, a history, and a player role that sees only what is revealed.
$ eidos install @The-Virtual-Panda/worldIn the app: New Root, then pick it from the list.
Download Eidos MD, start from the game framework, and give your core mechanic its own page. It is free, and your pages stay in your project.
Free for macOS, Windows, and Linux. Your files stay plain text in a folder you own.