You decide what happens. Claude writes it. The dice decide how it goes.

How Loom works

A story in Loom is a chain of passages. You write a short line saying what happens next, called a beat, and Claude writes the passage: a few paragraphs of prose in the story's voice. Then you write the next beat, and so on. You steer; Claude writes.

Behind the scenes, after every passage, a helper called the Chronicler reads what was written and updates the story's notes: who's who, where they are, what they want, what's still unresolved. That's how a story of hundreds of passages still remembers a promise made in chapter one.

Your first story

After signing in you land in the library, your shelf of stories. The one you worked on last sits at the top under Continue, with where it left off. Below are all your stories, as covers or as a list (the two buttons beside the search box switch between them).

• Try the sample. An empty library offers Mother of Learning: The Fourth Looper, a ready-made starter with a cast, rules and a "How to play" guide. It's your own copy to play with. Reading costs nothing.
• Start your own. Tap New story and write a premise: a few lines about the world, your main character and their situation. Claude can draft a title, a style guide, some characters and places, and ideas for the opening. Change anything you like, or start blank.
• Build the world first. Build the world first… in the same dialog has Claude ask you a few questions, then draft the people, places and things of your story for you to review before you begin. See Building a world.

The reader, piece by piece

Open a story and it fills the screen. Tap a number on the picture, or a line in the list, to see what each part does.

Writing your first beat

Tap the box at the bottom (What happens next?), type a line, and send it. That's a beat. It can be:

• Something you do: I follow her into the market, keeping my distance.
• Something you say: "You knew the whole time, didn't you?"
• Something that happens: The bridge gives way.

Short is fine. Claude fills in the moment around it: the setting, other people's reactions, the feel of it.

Three shortcuts

• Ideas. The chips above the box are three suggestions for what could happen next. Tap one and it loads into the box, so you can change a word before sending.
• Keep going. No idea what happens? Tap Keep going (or send an empty box) and Claude carries on from the last sentence.
• Write it yourself. Write this passage myself switches the box to plain writing. Your passage joins the story, and Claude picks up from your words next time.

Each passage costs about 2.6¢ on the default settings. Ideas cost about a tenth of a cent.

While Claude writes

The passage appears word by word. A few things worth knowing:

• Leaving is safe. The passage is written on the server, not in your browser. Lock your phone, lose signal, go back to the library: it still finishes and saves, and it's there when you return.
• Stop ends it early. Nothing is saved unless you choose Keep what was written, which keeps the part so far as the passage. The same choice appears if writing fails partway.
• One at a time. A story writes one passage at a time, so a second device waits for the first.

Changing a passage

Don't like what Claude wrote? Tap the passage for its menu:

• Rewrite (the latest passage) writes it again from the same beat. The old version is kept as a take; flip between takes with ‹ ›. After the first rewrite the button reads Another take.
• Edit lets you change the words yourself. Save, and it's yours.
• Remove and Rewind to here take passages away. They say exactly what goes before anything happens.

The menu also shows what that passage has cost so far, every take included.

Reading comfortably

Aa at the top of a story sets text size, theme, reading font, line spacing and line width. For more, Settings → Appearance has ten themes (from Linen and Sepia to Night Library and Blackout), fourteen reading fonts, any Google Font or a font file of your own, and book-style indented or spaced paragraphs.

Themes and fonts follow your account to every device. Text size and line width stay per device, so a phone and a monitor can each be just right.

Loom remembers where you stopped reading in each story.

Your first campaign

A campaign is a story where your beats are things your character tries, and dice decide how they go. Claude still writes every passage; the dice only decide what it must write. Start from any story, even one you're halfway through.

Open Backstage → Sheets, choose your character and tap Make a sheet. The quickest way is Draft with Claude (about 0.05¢): it reads the character's note and fills in scores, HP, armour, skills and gear for you to check. Or tap Standard array and arrange the numbers yourself. Save.

On the same tab, open Play as a campaign, tick Play this story as a campaign and Save. The box now asks What do you do?

Type an action, such as I slip past the guard while his back is turned, and send it. Loom works out whether it needs a roll. If it does, the passage waits for you:

Once the dice are in, Claude writes the passage, and it has to follow them: a failed sneak is written as a failure. Afterwards the Chronicler updates the sheet (a bruise, a coin purse, some XP), and a rewind takes those changes back.

Your stories are safe

• Nightly backups of every story, kept for two weeks on the server.
• Export any story from Backstage → Story → Export: EPUB for e-readers, Word, Markdown, or a Loom backup that keeps everything and can be imported back.
• Download all stories in Settings gives you every story in one zip.

Words you'll see

Beat

Your line saying what happens next.

Passage

What Claude (or you) writes from a beat: a few paragraphs.

Take

One version of a passage. Rewriting makes another; all are kept.

Chapter

A run of passages under one title, told by one storyteller.

Storyteller

Who tells a chapter: the narrator, or a character in their own voice.

Chronicler

The background helper that keeps the story's notes current after each passage.

Story bible

Those notes: characters, places, threads, "Right now" and the story so far.

Backstage

The panel (sliders icon) holding the bible, your notes and the story's settings.

Thread

An open question or promise in the story. Also the line down the reader's margin.

Knot

A mark on that line for each passage you steered.

Branch

A copy of a story up to a passage, for trying a "what if".

Sheet

A character's game record: scores, HP, armour, what they carry, what they can do.

Campaign

A story played as a game: your beats are actions, and dice decide how they go.

Check

A roll to see whether something works: a d20 plus a bonus, against a difficulty (DC).

Referee

The helper that decides what an action needs rolling. It never rolls or decides the result.

GM roll

A roll made in secret, so you learn what happens but not the number.

Host

The owner of a story played together: they invite players and pay for it.

That's everything for a first story, and for a first campaign once you've read the next section. When you're ready for more control, carry on below.

Beats that steer well

Claude takes a beat literally and fills the rest with judgement. The best beats say what happens and leave how to the writing, or to a director's note. Pick a kind of beat:

Good habits

• One or two moves per beat. Five things in one beat get crammed into one passage.
• Edit the ideas. They're built from what the characters want and the open threads. Tapping one and changing a word is often the best of both.
• Use Keep going for momentum, and a beat when you want to turn the story.

Director's notes

The note icon left of the box opens the director's note: guidance about the next passage that isn't part of the story. "Slow down and stay in the moment." "Keep it under three paragraphs." "More of Reyes's dry humour."

• A note applies to the next passage only, unless you tick Keep for every passage.
• Below the note are suggested notes; tap one to use it.
• Tap a passage's knot on the thread to see the beat and note behind it, so you can see why it turned out as it did.

Plans, secrets and the scratchpad

Backstage → Notes holds three kinds of note, each treated differently:

Secrets work with storytellers: a chapter told by someone who doesn't know a secret keeps it out of their thoughts, while a narrator can hint at it.

The story bible

Backstage → Bible is what Claude knows about your story, kept current by the Chronicler after every passage.

• Now: where things stand right now, and the current chapter.
• Characters: description, what they want, relationships, how they talk.
• Places and things, Threads (open questions and promises) and Story so far.

What you write is protected. Edit anything that drifts. The Chronicler adds to entries but never rewrites what you wrote, and never merges two of your entries.

The consistency check

After each passage the Chronicler compares it with the bible. A clear contradiction shows under the passage with three choices:

• Rewrite with this fixed when the passage is wrong.
• Update the Bible when the passage is right and the notes are wrong. Claude proposes corrected notes; you tick, edit and apply them. Nothing changes until you do, and what you apply counts as your own writing.
• It's fine to dismiss it.

Threads

The Chronicler keeps a list of open threads. Claude keeps them in mind, and at least one idea picks one up. Resolve, reopen or add threads yourself to point the story somewhere. They're listed quietest first; see Planning ahead.

Context: what Claude sees

Backstage → Context shows exactly what goes to Claude for the next passage. When a passage forgets something, look here first.

Planning ahead

Backstage → Plan is for where the story goes next.

Chapters

Every chapter so far, with its length, storyteller and what the summaries say, and Read it to jump there. Below, Coming next: the chapters you plan to write, in order, each with a title, what happens and who tells it. Claude reads them with your Plans and lets the story lead toward the first, without starting it early or giving it away.

• Suggest directions offers three different ways the next chapter could go ~0.1¢. Plan this next adds one.
• Start this chapter now opens it as a new chapter. Once it begins, it leaves the plan.
• Save the plan when you're done. Each save changes what Claude reads before every passage, so the next passage re-reads the story once ~3.5¢.

Threads

Open threads, quietest first, with the passage each came from and the last one that moved it on. A thread that hasn't moved in eight passages is marked Quiet. Pick this up next puts it in the director's note for the next passage, so Claude returns to it without you writing the beat.

Characters

For each character, the chapters they appear in (darker means more of that chapter), what they want and their relationships. Trace their arc sums up how they've changed chapter by chapter, where they stand and what they want now ~0.1¢.

Building a world

Build the world first… in the New story dialog, or Build out the world… in Bible → Characters or Places and things for a story you've started.

1. Say what to build: characters, places, objects, factions, rules, history; how much (about 4, 8 or 14 entries); and anything Claude should know.
2. Answer a few questions, or skip them. Claude asks up to five things your premise leaves open, each with suggested answers to tap a fraction of a cent.
3. Review the draft: every entry (for characters, what they want and how they talk), secrets, plans, and for a new story a title and style guide. Untick what you don't want and edit the rest 2–5¢.

What you keep counts as your own writing: the Chronicler adds to it as the story goes, but never rewrites it.

Revising without fear

Every tool here keeps the old version somewhere, apart from Remove and Rewind, which ask first.

Select some words

• Expand turns the selection into a fuller version of the same moment: slower, with detail, thought or dialogue, two to four times as long.
• Say it differently rewrites it in other words at about the same length.
• Rewrite from here (latest passage) keeps everything before the selection and writes the rest again.
• Highlight saves the line to Backstage → Highlights.
• Picture this draws exactly that moment (see Pictures).

Which tool when

Rewind and Remove also take back what the Chronicler learned from those passages, so the notes match the story again. Their scene pictures go too, and the dialog says so. When you're unsure, branch first: it costs nothing and leaves the original alone.

Long stories and memory

Claude reads three things before each passage: the codex (the bible entries that matter), the story memory (summaries of older chapters) and the recent passages, word for word, so its prose matches yours. As a story grows, older passages fold into summaries.

Two settings in Backstage → Story decide the balance:

Most of each prompt is cached, so a bigger window costs less than it sounds. The bigger cost is changing the notes: an edit to the bible or codex makes Claude re-read the whole prompt once, about 3.5¢ on the default writer.

Pictures

With a Gemini key (an admin adds it), Loom draws scenes, portraits and places.

• A scene: tap a passage → Picture this scene, or select words → Picture this for that exact moment.
• Portraits: Bible → Characters → Draw a portrait. Places and things: Illustrate.

Write your art style in Story settings (up to 1,500 characters). Portraits start from a short description of how the character looks, so they keep to it.

Before drawing you choose the shape (portrait, square, landscape, wide, tall or panorama), the size (each with its price) and up to three guide pictures for looks or composition. Each story has an art style in Story settings.

Each character, place and passage keeps a few pictures (four by default). Use ‹ › to look through them and Show this one to choose; a chosen one is never cleared out. Backstage → Pictures is the story's library: use a picture for an entry, draw with it as a guide, make it the cover, download or delete it. Uploads only guide new drawings; they're never shown on an entry.

Prices on the default model: 3.4¢ at 1K, 5¢ at 2K, 11.3¢ at 4K.

Your Cast

Cast in the library holds characters that belong to you rather than to one story. Add one to a story from Bible → Characters → Add from your Cast; the story gets its own copy to grow with, and Update in Cast brings its changes back. To keep the original as it was, Save to Cast as new… adds the changed character as a new member instead. Portraits come along.

Import characters and Export… move characters in and out as Loom files, Character Cards (the PNG or JSON cards SillyTavern and Chub use) or Markdown. A card's lorebook comes with its character, and its notes join each story they're added to. Importing asks what to do with any name you already have: Add as new, Replace mine or Skip.

Character sheets

A sheet is a character's game record: six scores with their modifiers, level, HP, armour (AC), gold, XP, conditions, limited resources such as spell slots, what they carry and what they can do. Make one from Backstage → Sheets → Make a sheet: fill the scores with Standard array, Point buy (the points are counted for you) or Roll 4d6 for each, or let Draft with Claude fill the whole form from the character's note.

Claude reads the sheets before each passage, so a character can't use a sword they don't carry. What a character is sits with the story in Claude's cache, so sheets add only about 0.06¢ a passage. After each passage the Chronicler moves HP, conditions, items, gold and XP. A new ability or a changed score waits under Suggested by the Chronicler until you Apply it, and leveling up is always yours: Ready to level up appears when they have the XP.

−1 and +1 change HP by hand, and anything you change is yours: a rewind never undoes it. A Cast member can carry a starting sheet into every story they join. The Roll log lists every die ever rolled in the story.

5e rules

A story can play by D&D 5e, the 2014 rules or the revised 2024 ones, instead of the light sheet. Choose in the campaign card's Rules: Light d20, 5e (2014, SRD 5.1) or 5e (2024, SRD 5.2). The rules are the free System Reference Documents: twelve classes, nine species or races, and the SRD's backgrounds, feats, spells and items.

Make a sheet then opens the sheet maker: a class, a species or race, a background, the scores, skills and choices, spells and equipment. The server works out AC, HP, saves, attacks and spell slots from the rules as you go, and lists anything still missing under To finish. On the sheet, tap a spell slot or a use to spend it, and Level up when the XP is there (or, with milestones, when you give everyone a level). The server rolls new hit points if you choose Rolled by the server. A 5e sheet costs about what a light one does: about 0.01¢ more a passage.

Characters from D&D Beyond and Foundry VTT come into your Cast as 5e sheets, matched to the SRD by name; anything from a book the SRD doesn't cover stays as the character's own.

This work includes material from the System Reference Document 5.1 and the System Reference Document 5.2 by Wizards of the Coast LLC, licensed under the Creative Commons Attribution 4.0 International License (creativecommons.org/licenses/by/4.0). Loom Tabletop isn't published, endorsed or approved by Wizards of the Coast.

Campaigns: dice and fights

In a campaign, a referee reads each action and decides what it needs: an ability check against a difficulty, a saving throw to resist something, an attack against armour, or nothing at all. The server rolls every die from a secret seed for the story, so no number is ever made up, and Claude narrates the result as it fell.

Fights. When one starts, everyone rolls initiative and the Sheets tab shows the order and the enemies' HP, round by round. A natural 20 doubles the damage dice; a natural 1 always misses. When the enemies fall, their XP is shared out.

Your choices, in Play as a campaign: Roll my checks for me skips the wait, Keep the GM's rolls secret can be turned off, and House rules are a few lines of your own that the referee and Claude both read.

A roll waiting for you is kept on the server: close the page, lose signal, come back tomorrow, and it's still there. A rewind takes back what the dice did, but the rolls stay in the log, marked as rewound. A rewrite keeps the dice and just tells it again. Keep going, End the chapter and a passage you write yourself roll nothing.

Playing together

Anyone with an account on your server can join a campaign. In Backstage → Sheets → Party, add them by their username and give them a character, or Make an invite link and send it: whoever opens it picks a character nobody plays. The story appears in their library, marked Party · you play, with Your turn when their action or roll is wanted.

The host is the story's owner. Everything is paid from their Spending (the Party card shows what each player's turns cost), and only they can rewind, rewrite, end chapters or change settings. A round costs about the same as one passage, however many play.

Players read the story and the Bible (not Plans, Secrets or the host's notes), act for their own character, roll its checks and edit its sheet.

Characters no player plays (an enemy, a guide, a friend who's away) are played by the story: the referee decides what they do and the server rolls for them. Tick one in the Party card to play it yourself.

Pictures are the host's choice, in the Party card: players don't see them, see the story's scenes and portraits (the default), or see and draw them, paid by the host: scenes, and their own character's portrait, at 1K (about 3.4¢ each), up to a few a month each.

Layouts and devices

Wide and tall screens

On a window wider than about 900 pixels, Aa offers Focused (one column, Backstage sliding over it) or Panels beside the story (Backstage kept open around it).

• Drag a panel's ⠿ handle to another side, beside another panel, or to an empty edge.
• Drag a side's inner edge to resize it; double-click resets it. With the keyboard, focus the edge and use the arrow keys.
• Each panel's ⋯ menu does the same without dragging, and Start from offers ready layouts.
• Portrait and landscape windows keep separate layouts, so a 1080×1920 monitor can keep the Bible above the story while a wide one keeps it at the side.

Phones

Below 900 pixels the page is always Focused. Installed as an app (Share → Add to Home Screen on iPhone, menu → Install app on Android), it opens full screen and keeps opened stories readable offline.

E-readers

On a Kindle, open /kindle in its browser for e-ink pages with nothing to install. On a jailbroken Kindle with KOReader, the Loom plugin keeps stories as books, and brings writing, chapters, Expand, pictures, takes, branches and rewinds into the book. See the KOReader guide.

What it costs

Loom shows costs as you go: tap a passage for what it cost, see your month in Settings, and admins see everything in Admin → Spending. Try your own pace:

The levers, biggest first

• Effort (Story settings). Thinking is billed as writing: medium costs about 40% more than low, high more than double.
• The writer model. Haiku is a tenth of the price; worth a try on a chapter to compare.
• Deep review model (Admin → Models and keys). Running the chapter-end review on Haiku saves about 20%.
• Rewrites and takes each cost a full passage.
• Picture size. 4K costs more than three 1K pictures.
• Prompt cache (Admin). Automatic is right for almost everyone: it uses a cheaper short cache only while you write quickly.

Admins can set monthly spending limits. When one is reached, writing pauses and reading carries on.

Comparing writers admins

To judge which model writes your story best, without knowing which is which:

1. Type a beat, then tap Compare writers under the box.
2. Choose two writers and their effort, then Write both. They appear side by side as A and B, in a random order.
3. Choose A is better, About the same or B is better. Only then are the models named.
4. Add A to the story or Add B to the story: that one becomes the next passage, and the other is kept as a take.

Admin → Compare writers does the same as a sandbox on any of your stories, adding nothing, and keeps the score per model and effort. A comparison costs about two passages; the writer your story doesn't normally use can cost up to twice its usual price, since nothing is cached for it yet.

Keeping Loom up to date admins

Loom can update itself from GitHub once whoever runs the server has set up the updater (one command, in tools/update/README.md). Then Admin → Updates chooses what it does:

• Off: no checks; Check now still looks once.
• Tell me: Admin and the library say when there's a new version, with What's new for each one since yours. Nothing installs until you press Update now.
• Install by itself: once nobody has used Loom for 10 minutes, never mid-passage.

An update takes a minute or two. It copies the database first, and if the new version doesn't start, the old one comes back with your stories as they were.

Shortcuts and small things

When something goes wrong