Stop wasting AI tokens on spell checking. LexiLint's offline spell checker catches typos instantly without consuming any API credits. Works with Claude Desktop, ChatGPT, Cursor, and any AI assistant that supports the Model Context Protocol (MCP).
💰 Spell checking: Zero tokens, zero cost, unlimited usage
The Model Context Protocol (MCP) is an open standard that allows AI assistants to connect to external tools and data sources. Think of it as a universal plugin system for AI.
Instead of the AI being limited to what it knows, MCP lets it:
LexiLint MCP provides three tools to AI assistants:
spell_check — Check text for spelling errors (100% offline, free)grammar_check — Check grammar with AI (BYOK, your API key)check_text — Combined spell + grammar checkingSpell checking doesn't need AI. Stop paying for something a local dictionary can do instantly.
Ask AI to check spelling
Use offline spell_check tool
Save your tokens for complex grammar analysis where AI actually adds value. Let LexiLint handle the simple stuff for free.
Check your prompts and messages for typos before sending them to Claude, ChatGPT, or any AI. Get better responses with error-free inputs.
AI-generated text can have hallucinations and errors. Use LexiLint to proofread code comments, documentation, emails, and content created by AI.
Spell check runs 100% offline. Grammar check goes directly to YOUR AI provider (you bring your own API key). LexiLint never sees your text.
Free: English (US & UK). Premium: +6 languages (Spanish, French, German, Polish, Russian, Turkish). Perfect for international teams.
Spell checking is instant (offline). Grammar checking takes 2-5 seconds depending on text length and AI provider speed.
Spell checking uses ZERO AI tokens — runs 100% offline with local dictionaries. Save $1.50-2.00 per 100 checks compared to asking AI. Grammar check uses your API key with Gemini's free tier.
Claude Desktop is Anthropic's official desktop app for Claude AI. It has built-in MCP support.
Open your Claude Desktop config file:
~/Library/Application Support/Claude/claude_desktop_config.json%APPDATA%\Claude\claude_desktop_config.jsonAdd LexiLint to the mcpServers section:
{
"mcpServers": {
"lexilint": {
"command": "npx",
"args": ["lexilint-mcp"]
}
}
}Restart Claude Desktop
Quit Claude completely (⌘Q on Mac) and reopen it.
Test it!
In Claude Desktop, type: "Check this text for spelling: Thiss is a tesst"
Claude will use LexiLint's spell_check tool and report the errors.
LexiLint MCP works with any tool that supports the Model Context Protocol:
npx lexilint-mcp and connect via stdioAsk your AI assistant:
"Check this text for spelling errors: Thiss is a tesst with errrors"
The AI will use LexiLint's spell_check tool and return:
Found 3 spelling errors:
• "Thiss" at offset 0
→ suggestions: This, Hiss, Thins
• "tesst" at offset 11
→ suggestions: test, tests, Tess
• "errrors" at offset 22
→ suggestions: errorsConfigure your API key in settings (one-time setup). Then ask:
"Check this for grammar: This are incorrect grammar"
The AI will use LexiLint's grammar_check tool with your API key and return detailed grammar suggestions.
"Proofread this entire paragraph for both spelling and grammar errors"
The AI can use the check_text tool to run both checks at once.
| Feature | Free | Premium |
|---|---|---|
| Spell check (en-US, en-GB) | ✓ Offline, unlimited | ✓ |
| Grammar check with Gemini | ✓ BYOK — free key at aistudio.google.com | ✓ |
| Multi-language spell check | ✗ | ✓ es, fr, de, ru, pl, tr |
| Multi-language grammar | ✗ | ✓ |
| OpenAI GPT-4 grammar | ✗ | ✓ BYOK |
| Anthropic Claude grammar | ✗ | ✓ BYOK |
Premium: $29.99 lifetime or $2.99/month
Get Premium
Model Context Protocol (MCP) is an open standard that allows AI assistants to connect to external tools and data sources. LexiLint's MCP server provides spell and grammar checking capabilities to Claude Desktop, ChatGPT, Cursor, and other MCP-compatible AI assistants.
Add LexiLint to your claude_desktop_config.json file with this configuration: {"mcpServers": {"lexilint": {"command": "npx", "args": ["lexilint-mcp"]}}}. The config file is located at ~/Library/Application Support/Claude/claude_desktop_config.json on macOS or %APPDATA%\Claude\claude_desktop_config.json on Windows.
Yes! Spell checking is 100% offline — no API key needed, and your text never leaves your machine. Grammar checking uses your own API key (BYOK) and sends text directly to your chosen provider (Google Gemini, OpenAI, or Anthropic). Google Gemini has a free tier.
LexiLint MCP works with any AI assistant that supports the Model Context Protocol (MCP). This includes Claude Desktop (official Anthropic app), ChatGPT desktop with MCP plugin, Cursor IDE, Zed editor, and any other MCP-compatible tool.
Yes! Spell checking (English US & UK) is 100% free and works offline. Grammar checking requires your own API key (BYOK) — Google Gemini offers a free tier. Premium features ($29.99 lifetime or $2.99/month) unlock 6 additional languages and multi-provider support (OpenAI, Anthropic).
Free: English (US & UK). Premium: +6 languages (Spanish, French, German, Polish, Russian, Turkish). Both spell checking and grammar checking support all 8 languages.
Install LexiLint MCP in under 2 minutes. Works with Claude Desktop, ChatGPT, Cursor, and more.
Open source • Privacy-first • No data collection