Vale

Vale is a command-line tool that brings code-like linting to prose. It's fast, cross-platform (Windows, macOS, and Linux), and highly customizable.

At a Glance: Vale vs. <...>

NOTE: While all of the options listed below are open-source (CLI-based) linters for prose, their implementations and features vary significantly. And so, the "best" option will depends on your specific needs and preferences.

Functionality

Tool Extensible Checks Supports Markup Built With License
Vale Yes (via YAML) spelling, style Yes (Markdown, AsciiDoc, reStructuredText, HTML, XML) Go MIT
textlint Yes (via JavaScript) spelling, style Yes (Markdown, AsciiDoc, reStructuredText, HTML, Re:VIEW) JavaScript MIT
RedPen Yes (via Java) spelling, style Yes (Markdown, AsciiDoc, reStructuredText, Textile, Re:VIEW, and LaTeX) Java Apache-2.0
write-good Yes (via JavaScript) style No JavaScript MIT
proselint No style No Python BSD 3-Clause
Joblint No style No JavaScript MIT
alex No style Yes (Markdown) JavaScript MIT

The exact definition of "Supports Markup" varies by tool but, in general, it means that the format is understood at a higher level than a regular plain-text file (for example, features like excluding code blocks from spell check).

Extensibility means that there's a built-in means of creating your own rules without modifying the original source code.

Benchmarks

This benchmark has all three tools configured to use their implementations of the write-good rule set and Unix-style output. This benchmark runs Vale's implementation of proselint's rule set against the original. Both tools are configured to use JSON output.
This benchmark runs Vale's implementation of Joblint's rule set against the original. Both tools are configured to use JSON output. This benchmark has all three tools configured to perform only English spell checking using their default output styles.

All benchmarking was performed using the open-source hyperfine tool on a MacBook Pro (2.9 GHz Intel Core i7):

$ hyperfine --warmup 3 '<command>'

The corpus IDs in the above plots—gitlab and ydkjs—correspond to the following files:

  • A snapshot of GitLab's open-source documentation (1,500 Markdown files).

  • A chapter from the open-soure book You Don't Know JS.

GitHub

https://github.com/errata-ai/vale