---
title: File formats
description: How lawlint reads plain text, Markdown, and Word documents — and what it preserves when it writes them back.
icon: file-text
---

The CLI lints plain text, Markdown, and Word documents.

| Format | Extensions | Notes |
| ------ | ---------- | ----- |
| Plain text | `.txt`, anything else | Linted verbatim. |
| Markdown | `.md` | Fenced code blocks are skipped automatically. |
| Word | `.docx` | Text is projected out for linting; `--fix` writes back tracked changes. |

Passing `-` — or no file at all — reads stdin.

## Markdown

For a `.md` file, lawlint strips fenced code blocks before linting, so a code
sample full of em dashes and `delve` never produces findings.

Piped input has no filename to infer from, so ask for it:

```sh
cat draft.md | lawlint --markdown
```

## Word documents

`.docx` files are read into the same text model as everything else. With
`--fix`, machine-applicable fixes are written back as native Word **tracked
changes**, each accompanied by a review **comment** naming the rule — so every
change lands in Word's normal review flow and can be accepted or rejected one
at a time.

Everything else in the document is preserved byte for byte: styles, numbering,
headers, embedded images, and any tracked changes already in the file.

:::warning[Fixes that cross runs are skipped]
Word splits a paragraph into *runs* whenever formatting changes mid-sentence. A
fix whose span crosses a run boundary — a bolded word in the middle of a
flagged phrase — is reported and skipped rather than applied. This is a current
limitation, not a silent failure: the finding still appears in the output, it
simply is not auto-fixed.
:::

## Stdin

```sh
cat memo.txt | lawlint - --format json
lawlint < memo.txt
```

Reading stdin is what makes lawlint composable in editors and pipelines — see
[Continuous integration](/docs/guides/ci). Since there is no file to write
back to, `--fix` has nothing to modify; use `--format prompt` or `--diff`
instead.