LexiLint MCP
Spell and grammar checking for AI assistants via Model Context Protocol (MCP).
Works with Claude Desktop, Cursor, ChatGPT, and any MCP-compatible tool.
Features
- 🔒 100% offline spell check — uses nspell with local dictionaries. Zero tokens consumed. Zero API calls. Works without internet.
- 🤖 BYOK grammar check — bring your own Gemini (free tier), OpenAI, or Claude API key. Your text goes directly to your chosen provider.
- 💰 Zero token cost for spell check — stop wasting AI tokens on typo detection
- 🌍 8 languages — English (US/UK), Spanish, French, German, Polish, Russian, Turkish
- ⚡ Instant results — no latency, no rate limits, unlimited usage
Installation
Claude Desktop / Cursor / ChatGPT
Add to your MCP config:
{
"mcpServers": {
"lexilint": {
"command": "npx",
"args": ["-y", "lexilint-mcp"]
}
}
}
npm
npm install -g lexilint-mcp
Usage
Once installed, your AI assistant can use these tools:
spell_check— check text for spelling errors (100% offline)grammar_check— check text for grammar issues (requires API key)
Example
"Use the spell_check tool to check this text: 'Ths is a tset'"
The spell check runs locally — no tokens consumed.
Token Cost Comparison
| Method | Cost per 500-word check |
|---|---|
| Ask AI directly ("fix typos in this") | ~$0.02 (GPT-4) / ~$0.015 (Claude) |
| LexiLint MCP spell_check | $0.00 |
Grammar Check Setup
Grammar checking uses your own API key (BYOK):
- Get a free Google Gemini API key
- Set the environment variable:
{
"mcpServers": {
"lexilint": {
"command": "npx",
"args": ["-y", "lexilint-mcp"],
"env": {
"GEMINI_API_KEY": "your-key-here"
}
}
}
}
Supported providers: GEMINI_API_KEY, OPENAI_API_KEY, ANTHROPIC_API_KEY
Links
License
MIT