Inform 7 is Graham Nelson's design system for parser interactive fiction, released in 2006. You write in plain-English rules — “The Cabin is a room. A brass lantern is in the Cabin.” — and Inform builds a simulated world the player explores by typing commands. It compiles to the Glulx or Z-machine virtual machines, and was open-sourced in 2022 under the Artistic License 2.0.

What does Inform 7 compile to, and can wilds.ai play it?

Inform 7 compiles to a Glulx or Z-machine story file. wilds.ai runs those story files in-app — a shareable page, no download, cross-device save, and a parser that plays the canonical prose verbatim. An optional AI layer adds scene art, ambient audio, and per-character voices on top; the text you wrote never changes.

How is Inform 7 different from Twine and ink?

Inform 7 is parser interactive fiction: the player types commands ("take lantern", "go east") against a simulated world model. Twine is passage-and-link — the reader clicks hyperlinks between passages. ink is inkle's choice-scripting language — the reader picks from listed choices. wilds.ai hosts all three as one Stories family sharing the same reader and optional AI layer.

Inform 7 · IF engine

Inform 7 worlds,write + play in-browser

Inform 7 is Graham Nelson's natural-language system for parser interactive fiction. Write in plain-English rules, compile to Glulx or Z-machine, and play in-app with cross-device save and the same optional AI layer: scene art, ambient audio, and per-character voices. Plays verbatim. Keep and export your story file.

What is Inform 7?Write in Inform 7 Play Inform 7 games

Write in natural language
Compiles to Glulx / Z-machine
Tag-driven art + audio
Keep + export your file

Play Inform 7 games online

Inform 7is Graham Nelson's natural-language system for parser interactive fiction — you write a world in plain-English rules, and Inform simulates it as a game the player explores by typing commands. On wilds.ai it's a first-class Stories engine: play compiled Glulx and Z-machine stories in-app with no download, the canonical prose verbatim, and an optional AI layer on top.

Browse stories →Write in Inform 7

From plain-English rules to a playable world

Write in natural language
Inform 7 reads like English. "The Cabin is a room. A brass lantern is in the Cabin." builds a simulated world — rooms, objects, and rules the player explores by typing commands.
Compile to Glulx or Z-machine
Inform turns your source into a story file for the Glulx or Z-machine virtual machine. That file is the playable game: portable, self-contained, and yours to keep.
Play on wilds, verbatim
wilds.ai runs the story file in-app with cross-device save. The canonical prose plays word for word; an optional AI layer adds scene art, audio, and voices. Export your file anytime.

Does Inform 7 use AI?

Inform 7 itself doesn't — it's a pure, open-source authoring system. On wilds.ai, a hosted Inform 7 story gets an optional AI layer: scene art for a room, an ambient and music bed for a mood, and per-character voices for the people you wrote. The parser prints your prose unchanged; the AI only fills the margins you choose to enhance.

The source reads like English

"Lakeside Cabin" by Edith Vale

The Cabin is a room. "Rain ticks on the tin
roof. A door leads east to the porch."

The Porch is east of the Cabin.

A brass lantern is in the Cabin. The lantern is
lit. The description is "Dented, and somehow
still burning."

Instead of going east in the dark:
    say "The night outside is total. Better to
    carry a light."

Every line is a rule Inform compiles into a simulated world:

The Cabin is a room. creates a place the player can stand in.
A brass lantern is in the Cabin. drops an object you can take, examine, and carry.
Instead of going east… is a rule that bends the world model.

Compile it to a Glulx or Z-machine story file, and wilds plays that file verbatim — parser and all.

How an Inform 7 story reaches wilds

Inform 7 sourceplain-English world rules

CompileGlulx or Z-machine story file

Play on wildsverbatim prose · optional AI layer

Natural-language authoring

Inform 7 is Graham Nelson’s system for writing IF in plain-English rules. You describe a world; Inform simulates it. The result is a parser game where players type what they want to do.

Compiles to Glulx + Z-machine

Your source compiles to a Glulx or Z-machine story file — the same portable formats that have carried interactive fiction for decades. The file is the game, and it runs anywhere those VMs run.

Plays on wilds, word for word

wilds hosts the compiled story and runs it in-app: a shareable page, no download, cross-device save, and a parser that prints your canonical prose verbatim. Nothing about the text is rewritten.

Optional AI layer

Layer on the same optional enhancements as every Stories engine — generated scene art for a room, an ambient + music bed for a mood, a per-character AI voice for an NPC. Every enhancement is optional and sits beside the original text.

Your file stays yours

wilds is a place to host and enhance, not a lock-in. Keep your source, recompile in Inform whenever you like, and export your story file from wilds at any time.

One Stories family

Inform 7, ink, and Twine are sub-engines of the same Stories family on wilds, sharing the runtime, the reader, and the AI layer. Author in the tool you love; play it here.

Inform 7 vs. Twine vs. ink

Feature	Inform 7	Twine	ink
Authoring model	Natural-language world rules	Passage-and-link	Choice scripting
How the player acts	Types commands (parser)	Clicks hyperlinks	Picks listed choices
Compiles / runs as	Glulx / Z-machine story file	HTML story format	ink → JSON runtime
Open source	Yes — Artistic License 2.0 (2022)	Yes	Yes — MIT
Plays on wilds with AI layer	Yes	Yes	Yes

Bring an Inform 7 story to wilds

Start a story in Inform 7's natural-language rules, or browse the ink stories and classic parser adventures already live on wilds. Inform 7 joins ink and Twine as one Stories family — one runtime, one reader, one optional AI layer.

Write in Inform 7 →Browse all stories →

References

Prefer choice-based stories? wilds.ai also supports ink → · and Twine → · Browse all stories →

>Inform 7 worlds,write + play in-browser