# What is a game design document (GDD)?

A game design document (GDD) describes a game’s vision, rules, systems and content for the team that builds it.

Updated on 22 October 2026.

## How it works

Studios long wrote one large GDD before production, as Tim Ryan’s 1999 guide in Game Developer describes. Most teams now keep a living GDD: a short overview that links to one document per system, character or level, each with an owner.

A GDD serves design, art, code, audio and production at once, so it works best when each part is easy to find, dated, and clear about what is decided and what is still being explored.

## An example

A small team’s GDD has an overview page linked to documents for combat, the economy, the main characters and the first level. The economy document holds the balance sheet the designers tune, not a copy of it.

## Common mistakes

- Writing one long document nobody reads past the first pages.
- Letting the GDD and the game drift apart without dating changes.
- Keeping balance numbers in a separate spreadsheet the GDD only describes.

## In Nodary

In Nodary, a GDD is a set of linked documents on the project’s map, with balance sheets that compute, branching dialogue, string tables, moodboards and picture review in the same workspace. A free GDD template of linked Markdown files, in 12 languages, imports in one step.

**What Nodary does not do:** dialogue conditions and variables are not modelled: branching dialogue is written, played through and exported to Yarn Spinner.

- [Game design document software](https://nodary.ai/game-design-document)
- [Free GDD template](https://nodary.ai/templates/game-design-document)

Try it on your own documents. The Free plan needs no card. [Create a free workspace](https://nodary.ai/sign-up)

## Sources

- [The Anatomy of a Design Document, Tim Ryan, Game Developer, 1999](https://www.gamedeveloper.com/design/the-anatomy-of-a-design-document-part-1-documentation-guidelines-for-the-game-concept-and-proposal)
- [Game design document, Wikipedia](https://en.wikipedia.org/wiki/Game_design_document)

## Related terms

- [Art bible](https://nodary.ai/glossary/art-bible): An art bible is the visual style guide of a game or production: the palette, shapes, light and references every artist follows.
- [Moodboard](https://nodary.ai/glossary/moodboard): A moodboard gathers images, colours and references to show the look and feel a project aims for, before the work is made.
- [Product requirements document (PRD)](https://nodary.ai/glossary/product-requirements-document): A product requirements document (PRD) says what a product or feature must do and why: the problem, users, goals, requirements and scope.
- [Localization string table](https://nodary.ai/glossary/localization-string-table): A localization string table stores every text of a game or app under a key, with one column per language.

https://nodary.ai/glossary/game-design-document