You review the changes, not the document
The preview lists every paragraph that moved, old text above and new text below, with the changed stretch highlighted. A forty-page specification with three edits is three things to read.
Get the document back edited,not retyped
Paste a specification into a chat window and you get prose back: correct, maybe, but stripped of the client template, the numbering, the tables and the logo you now have to rebuild by hand. A Khint agent can hand back the file itself, edited.
The rewrite is five minutes,
putting it back is an hour
One terminology pass through forty pages in the company template: the AI part is easy. The expensive part is copying the answer back paragraph by paragraph and noticing on page 19 that a numbered list turned into bullets. That reassembly is why the document stays as it is.
Same file, one paragraph changed. The original is never opened for writing; the edit lands in a new copy.
From a file on disk to an edited copy
One switch in the agent editor, then your usual shortcut.
Tell the agent it works on a file, and what it hands back
In an agent’s editor, set its input source to Document. A second control appears underneath: what the agent gives you. Leave it on Text and the result lands in your clipboard. Switch it to The edited file and the same document comes back rewritten instead.
Run it on the file, from the palette or its shortcut
Nothing else changes about how you launch it. The agent can ask for a file each run — a drop zone, your recent files, a browse button — or stay pinned to one document. Before the run starts the palette shows what the edit will cost, so a forty-page specification never surprises you. Cancel there and nothing is written or charged.
The model proposes wording, Khint writes the file
The AI never sees a .docx. It receives the document as numbered paragraphs and returns only the ones it changed. Every byte of file structure is written locally by Khint from your original: the template, the styles, the theme, the images, the headers and footers are copied straight through. A model can suggest better wording; it has no way to corrupt your document.
Read the diff before anything leaves your machine
The run opens a preview listing every paragraph that changed, old text above, new text below, with the changed stretch highlighted. Nothing is sent anywhere: from there you download the edited copy where you want it, reveal it in your file browser, or ignore it because the rewrite wasn't what you wanted.
Untouched paragraphs stay byte for byte identical
This is the part a chat window can't offer. Paragraphs the agent left alone aren't regenerated or reflowed: they're the original bytes. A client template, a numbered requirements list, a table of contents and a logo in the header survive a terminology pass without anyone checking them. You review the changes, not the document.
Inside one document pass
What changed, what the formats keep, where the run stops rather than guessing, and what actually crosses the wire.
Four formats come back as themselves
The Office three are rewritten on your Mac, text node by text node. A PDF stores positioned text rather than paragraphs, so each edited line is repainted where it sat.
Word
PowerPoint
Excel
PDFIt refuses rather than half-finishing
Each of these stops the run with a message instead of a partial result. Silently truncating a contract and calling it edited would be the worse answer.
The model never sees a .docx
It receives numbered paragraphs and returns only the ones it changed. Every byte of structure is written locally from your original, so a model can propose wording and has no way to corrupt the file.
Two ways to do the same pass
The AI work is identical in both columns. Everything that differs happens after it.
Copy into a chat window
The AI pass works. What comes back is prose, so the document is yours to rebuild.
- You get text back, so the template, the styles and the images are gone.
- Every paragraph is regenerated, so every paragraph needs checking.
- Rebuilding the document is manual, and it's the longest part of the job.
Run a Khint agent on it
The same AI pass, and what comes back is the file itself, as a copy beside yours.
- You get the same file back, edited, as a new copy beside the original.
- Only the paragraphs that changed were written, so you review a short diff.
- There's no reassembly step, because nothing was taken apart in the first place.
Where it stops, on purpose
A document editor that guesses is worse than one that refuses. Each of these is a deliberate stop.
It refuses rather than half-finishing
An empty document, a single paragraph longer than 5,000 characters, or a document longer than 150,000 characters stops the run with a clear message. Silently truncating a contract and calling it edited would be the worse answer.
Nothing to change means no file
If the agent comes back proposing only the wording that was already there, you get a "nothing to change" result instead of a new file to compare against the old one.
A file saved mid-run isn't written over
If the document changes on disk while the agent is working, the write is refused. The edits are addressed by paragraph position, and a document that moved underneath them would take the right edits in the wrong places.
PDF limits are shown, not hidden
In a PDF, text is repainted into the space it occupied. Where that can't be done faithfully, because the new text won't fit, because the background isn't one flat color, or because a character can't be drawn in the standard font, the spot is flagged in the preview rather than quietly approximated.
The original is never
opened for writing
Every run writes a new file beside your other Khint outputs and leaves the document you were handed exactly as it arrived. If the rewrite isn't what you wanted, there's nothing to undo.
See documentsYour source file is never opened for writing
The result is a new copy, with an (edited) suffix
Untouched paragraphs are the original bytes
A small fix touches only the characters that moved
Styles, tables, images and headers copied through
The diff is shown before anything is saved anywhere
Word, PowerPoint and Excel rewritten, PDF repainted
It refuses rather than truncating a document
The rest of Khint
The file is both the input and the output. These three are what runs in between.
Common questions
Which file formats come back edited?
Word (.docx), PowerPoint (.pptx), Excel (.xlsx) and PDF. The Office formats are rewritten directly on your machine: only the text you asked to change is replaced, and every other part of the package (styles, theme, images, headers) is copied through unchanged. A PDF stores positioned text rather than paragraphs, so it's handled differently: each edited line is repainted in place, and any spot where that can't be done cleanly is flagged for you instead of being faked.
Does my original file get overwritten?
No. The source document is never opened for writing. Khint writes a new file next to your other Khint outputs, named after the original with an "(edited)" suffix, and a later run never overwrites an earlier result. From the preview window you can download a copy wherever you want it or reveal the file in Finder or Explorer.
What happens to formatting inside a paragraph I rewrite?
The unit Khint replaces is the text itself, not the paragraph's styling, so the paragraph keeps its own style, spacing and numbering. Inside a paragraph, a small fix touches only the stretch of characters that changed: a bold term or a link elsewhere in the same paragraph survives untouched. A full rewrite of a paragraph is the one case where intra-paragraph formatting isn't preserved, since none of the original wording is left to attach it to.
Can a workflow end with an edited document?
Not today. A workflow can start from a document, and its steps can write to Jira, Confluence, Linear, Notion, Slack or Gmail, but giving back the edited file is something you set on an agent and get when you run that agent. If you want a workflow to act on a document, point its trigger at the file and let the steps produce text or an integration write.
Hand over the next document as it is
Free with 300 credits a month, about 10 AI actions a day. No credit card. Word, PowerPoint, Excel and PDF, with your original left untouched.