What chaff does for each kind of document

chaff looks at different things depending on the kind of document (the genre). These pages show, for one kind at a time, what chaff finds and what it does not, on a real document and its real screen. They are written for people who have never used a command line.

chaff is the machine; people and AI do the reading

chaff checks text by fixed steps. The same text gives the same result every time. It never rewrites anything; fixing is the writer’s job.

Anything that needs the meaning to decide (does the conclusion say something?) is not decided by chaff alone. npx chaffjs test sends only the passages the machine narrowed down to an AI, and has it read them. Using an AI is your choice. Without one, every machine check still runs.

What kind of document do you have?

Pick the one closest to yours, and go to its page. Each page names the genre to use, runs chaff on a short sample and shows the real screen.

Your document, and its pageWhat chaff finds
Tech articles and blog posts: a tech article or a team blog postStock openings and closings, shapes of generated text, counts that do not match, links that go nowhere
Contracts and terms of service: a contract, terms of service or a privacy policyPeriods that run backwards, totals that do not add up, references to missing articles, skipped numbers, wrong weekdays
Internal rules and regulations: internal rules, regulations or official noticesSkipped article numbers, references to articles that are not there, a term defined twice
Business email: an email or a letter to a clientSentences too long to follow, stacked hedges, wrong weekdays, blanks left in
Meeting minutes: minutes or meeting notesWrong weekdays, skipped item numbers, counts that do not match, decisions with nobody behind them
Business reports: a monthly report, a white paper or an internal documentOpenings that fit any document, stacked hedges, passives that never say who acts, sentences that run too long
Payslips, bills and statements: a payslip, an expense claim, a bank statement, a bill, checkup results, a transcript, a delivery noteNet amounts, totals and balances that do not add up, dates in the wrong order, a booking or employee number written two ways
Manuals and API docs: a user guide, an API doc or a help pageLinks that go nowhere, images with no description, skipped heading levels, empty sections
Press releases and announcements: a press release or an announcementWrong weekdays, periods that run backwards, totals and breakdowns that do not add up
Papers and abstracts: a paper, an abstract or a conference submissionMixed British and American spelling, doubled words, references to missing figures

If none fits, find the closest genre on the genres page, which also shows which rules run for each kind. With no genre set, chaff reads a document as a tech article. When the file name or the content says otherwise, it suggests a genre on the screen.

Getting ready

chaff needs a tool called Node.js. You set it up once.

StepWhat to do
1Install the version marked LTS from nodejs.org. chaff needs Node.js 24 or later
2Open the window where you type commands: Terminal on a Mac, PowerShell on Windows
3Type node --version and press Enter. A number of v24 or higher means it is installed
4Type cd and a space, then the location of the folder that holds your document, and press Enter. On a Mac you can drag the folder into the window to fill in its location

Save the document as a plain text file ending in .md (Markdown). Start each heading line with # (as in ## Article 1 (Purpose)). For a Word document, paste the text into a text editor and save it from there.

npx chaffjs fetches chaff and runs it. There is nothing else to install. The first time, it asks whether it may fetch the package. Press y to go on.