Spell Checker MCP Server

Overview

A remote MCP server providing enterprise-grade spell checking and AI-powered grammar correction. Supports 53 languages with automatic detection, sub-50ms response times, and intelligent corrections using DeepSeek R1.

Languages

MCP Tools

<50ms

Response Time

The Problem

AI agents generating or processing text need reliable spell checking that:

Works across multiple languages without manual configuration
Provides precise error locations for targeted fixes
Distinguishes between spelling errors and grammar issues
Can automatically apply corrections when needed

Traditional spell checkers lack AI integration and multi-language auto-detection.

Solution

Three specialised tools for different use cases:

spell_check_analyze1

Error detection

spell_check_grammar1

AI grammar check

spell_check_correct1

Auto-correction

Tools

spell_check_analyze

Fast spelling error detection using Hunspell dictionaries:

Precise line and column positions for each error
Multiple correction suggestions per error
Language auto-detection or manual override
Sub-50ms response times (no AI involved)

spell_check_grammar

AI-powered grammar and style analysis using DeepSeek R1:

Grammar and punctuation error detection
Style improvement suggestions
Rule categorisation for each issue
Context-aware corrections

spell_check_correct

Automatic correction with document storage:

Fix spelling errors, grammar issues, or both
Corrected documents stored in R2
30-day retention with retrieval URL
Preserves original formatting

Features

53 Languages - Comprehensive Hunspell dictionary support
Auto-Detection - Identifies language automatically
DeepSeek R1 - 32B parameter model for grammar analysis
Edge Deployment - Global low-latency via Cloudflare Workers
OAuth Security - Google authentication for access control
R2 Storage - Corrected documents with 30-day retention

Architecture

Text Input → Language Detection → Hunspell Analysis
                                        ↓
                              Spelling Errors + Positions
                                        ↓
                    [Optional] DeepSeek R1 Grammar Check
                                        ↓
                    [Optional] Auto-Correct → R2 Storage

Use Cases

Content Generation - Ensure AI-generated content is error-free

Document Processing - Batch spell check uploaded documents

Multi-Language Support - Handle international content without configuration

Quality Assurance - Add spell checking to content workflows