Using Loom
Loom Guide

A guide to LoomEngine

You decide what happens. Claude writes it.

Loom turns a line from you into a passage of story, keeps track of everyone and everything in it, and remembers it all as the story grows. This guide walks through every part you can tap, type into or drag.

Part one

First steps

Everything you need to write and read a story. Nothing here costs more than a few cents.

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.

The short version. Type what happens. Read what Claude writes. Repeat. Everything else in this guide is there when you want more control.

Your first story

The library

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).

Two ways to begin
  • 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.
A good premise names a person, a place and a pressure. "A courier in a drowned city is handed a letter she isn't meant to read" gives Claude far more to work with than "a fantasy adventure".

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.

The Salt Bell Aa

Chapter one · Low Tide

The lamps along the quay guttered as Mara read the address twice. Salt hung in the air, and below the boards the tide worked at the pilings.

She folded the letter into her sleeve and walked, not ran, toward the bell tower.

Previously… Mara took a letter meant for the harbor master.

Then the bell on the watchtower rang twice, and every window on the quay went dark.

Hide in the chandleryClimb the towerKeep goingEnd the chapter
What happens next?
As Mara ▾Write this passage myself

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.

Start small. Rewrite and takes are all you need at first. The other tools are in Revising without fear.

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 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".

That's everything for a first story. When you're ready for more control, carry on below.

Part two

Going further

The tools that make long stories good: steering, structure, secrets, revision, memory, pictures and cost.

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:

I slip the letter back under the door and wait in the alley to see who collects it.

I do something sneaky.

A concrete action with an intention gives Claude a scene to build. "Wait to see who collects it" sets up the next moment without deciding it.

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.
Beat or note? The beat is what happens; the note is how it's told. "She lies to him" is a beat. "Let the reader see she's lying before he does" is a note.

Chapters and storytellers

The storyteller pill under the box (Narrator ▾ or As Mara ▾) starts a new chapter at any point: a title, who tells it, and optionally how it opens.

Points of view

Any character can tell chapters once you tick Can tell chapters on their profile (Backstage → Bible → Characters), where you also choose first person, close third or all-seeing third. A storyteller stays inside what they know: secrets they haven't learned are kept out of their head, and their ideas use their own wants. Each storyteller gets their own knot colour on the thread.

Use for this chapter instead changes who tells the chapter you're in.

Ending chapters

The End the chapter idea asks Claude to bring the chapter to a close in the next passage, using your beat if you typed one. Once a chapter has run a while, the Chronicler watches for a natural resting point; when it finds one, the idea lights up with its reason. After a chapter ends, the idea becomes Start the next chapter.

You can also tap any passage and choose Start a chapter here, or Rename chapter on one that already starts one.

Why chapters matter. At each chapter's end the Chronicler does a deeper review: it reads the whole chapter, tidies the notes, merges duplicates and closes finished threads. Regular chapters keep a long story's memory clean.

Plans, secrets and the scratchpad

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

NoteClaude sees it?Use it for
PlansYes, but never reveals it earlyWhere the story is heading: the twist in act three, who the traitor is
SecretsYes, with who knows each oneThings some characters know and others don't. Storytellers who don't know a secret can't think it
ScratchpadNeverYour own notes, reminders and ideas

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¢.

Plan loosely. A title and one line ("Mara follows the empty boat upriver") is enough for Claude to start leaning that way. The more you write in a planned chapter, the more firmly it steers.

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

ToolWhat changesWhat's keptCost
Rewrite / Another takeThe latest passage, written againEvery take (‹ ›)2.6¢
Rewrite from hereThe end of the latest passageThe earlier take2.6¢
Expand, Say it differentlyThe selected words, in any passageThe earlier take~1¢
EditWhatever you typeThe earlier takefree
Branch from hereNothing: a new story copies this one up to hereEverythingfree
RemoveThe latest passage goesNothing of itfree
Rewind to hereEvery later passage goesNothing of themfree

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:

SettingLarger meansDefault
Recent passages, word for wordCloser voice and continuity, a slightly bigger prompt8,000 tokens (about 10 passages)
Codex: lore Claude always hasMore characters and places always in mind4,000 tokens

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.

Edit the bible in batches. Fix five things at once, then write, rather than one edit between each passage.

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.

Portraits first. Characters' portraits go with every scene they appear in, so drawing the main cast once keeps them looking the same from picture to picture.

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.

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:

2.6¢a passage
$1.73a week
$7.48a month
$4.66a 100,000-word story (about 180 passages)

Estimates from Loom's measured cost study, at a mixed writing pace, with background work on Haiku 5.5. Real bills can run up to a third higher, and depend on your prices in Admin.

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.

Compare a few times. One passage says little. Ten rounds on beats you'd really write tell you whether a cheaper writer is good enough for your story.

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.

On a Kindle, the Loom plugin updates itself from your server too: opening Stories offers a newer plugin once a day, and Loom → Update the plugin checks whenever you like.

Shortcuts and small things

Do thisTo
Ctrl + Enter (⌘ + Enter on a Mac)Send the beat
EscClose a menu, Backstage or the reading settings, or deselect a passage
Arrow keys on a panel edgeResize it (hold Shift for bigger steps)
Double-click a panel edgeReset its size
Tap a knot on the threadSee the beat and note behind that passage
Tap the story titleContents, to jump between chapters
A few more things worth finding
  • Listen in a passage's menu reads it aloud; the read-aloud settings are in Aa.
  • Covers: pin any picture as a story's cover from its ⋯ menu in the library (Choose cover…).
  • Branches fold under the story they came from in the library; the ⑂ button shows them.
  • Import brings in a Loom backup, Markdown or plain text, and Loom summarises it over the next few minutes.
  • Whether your beats show between passages is a choice in Aa, for reading a story back as a book.

When something goes wrong

A passage stopped partway

Choose Keep what was written to keep it, then Keep going to finish it, or let it go and write again. The text waits for an hour, as long as the story hasn't moved on.

"This passage reached the length limit"

The writer ran out of room, usually at high effort. Use Keep going to carry on, or rewrite it at a lower effort.

Claude forgot something important

Check Backstage → Context for what Claude saw. Add the fact to the bible (a character's entry, or Now), or raise the recent-passages setting. Write it as a plain statement: "Mara's brother drowned three years ago."

A character knows something they shouldn't

Put it in Notes → Secrets and mark who knows it. Chapters told by someone who doesn't know it keep it out of their head.

"The server is busy right now"

Another request was saving at the same moment. Wait a few seconds and try again.

Writing has paused with a spending message

A monthly limit was reached. An admin can raise it in Admin → Spending; reading and editing still work.

This guide covers LoomEngine 2.16. The complete reference is the manual that comes with every install (README.md in the loom_engine folder).