About
llm-spell is both a library and command-line utility that corrects spelling mistakes using a Large Language Model (LLM). It is powered by llm.rb.
Motivation
This project was born while I was working on the documentation for a friend's open source project. After realizing how much manual effort was involved with traditional spell checkers I decided to see if I could leverage LLMs to make the process easier and also faster.
Compared to traditional spell checkers like aspell and hunspell,
llm-spell provides significantly more accurate suggestions with
far fewer false positives – eliminating the need to manually
ignore irrelevant corrections, and that often reduces the overall
time spent on correcting spelling mistakes.
I would call the experiment a success but I also realize this
approach is not for everyone, or every situation. For example,
my friend preferred to not use AI for this and instead we opted
to stick with hunspell – even though it meant more
manual work.
Features
- ✨ LLM-powered corrections – smarter spelling fixes than traditional tools
- 🤖 Fewer false positives – avoids flagging uncommon but valid words
- 🌐 Broad provider support – use OpenAI, Gemini, or xAI (Grok) out of the box
- 💻 Offline ready – run locally with Ollama and LlamaCpp, no cloud required
- 🔒 Privacy – keep sensitive text local with offline models
- 🛠️ Easy to use – provides an easy to use library and command-line utility
Library
#!/usr/bin/env ruby
require "llm"
require "llm/spell"
##
# Text
llm = LLM.openai(key: ENV["OPENAI_SECRET"])
text = LLM::Spell::Text.new("Ths is a smple txt with sme speling erors.", llm)
print "mistakes: ", text.mistakes, "\n"
print "corrections: ", text.corrections, "\n"
##
# PDF
llm = LLM.openai(key: ENV["OPENAI_SECRET"])
file = LLM::Spell::Document.new("typos.pdf", llm)
print "mistakes: ", file.mistakes, "\n"
print "corrections: ", file.corrections, "\n"
CLI
Configuration
The command line interface can be configured through the configuration file
located at $XDG_CONFIG_HOME/llm-spell.yml or ~/.config/llm-spell.yml. It
is also possible to provide the configuration at the command-line, but usually
it's more convenient to use the configuration file:
# ~/.config/llm-spell.yml
openai:
key: YOURKEY
gemini:
key: YOURKEY
xai:
key: YOURKEY
ollama:
host: localhost
llamacpp:
host: localhost
Usage
Usage: llm-spell [OPTIONS]
-p, --provider NAME Required. Options: gemini, openai, xai, ollama or llamacpp.
-f, --file FILE Required. The file to check.
-k, --key [KEY] Optional. Required by gemini, openai, and xai.
-v, --version Optional. Print the version and exit.
Demo
Start demo
