grammar-checker

grammar-checker is a rule-based Korean proofreading skill that detects and corrects spelling, spacing, grammar, and punctuation errors according to standard Korean language rules from the National Institute of Korean Language. It targets the common, hard-to-catch mistakes native and learning writers make — confusable forms like 되/돼, -ㄴ지/-는지, -ㄹ게, 던/든, 안/않, and 로써/로서 — as well as spacing around dependent nouns and auxiliary verbs, particle selection, verb endings, and punctuation misuse. The goal is not just to flag errors but to explain why each is wrong, so the user learns the underlying rule.

The skill follows a structured four-step workflow: receive text (directly, from a file, or from conversation context), check systematically by priority (spelling first, then spacing, grammar, and punctuation last), load reference documents (references/rules.md and references/common-errors.md) when an error is uncertain or a detailed explanation is requested, and present results in a fixed Markdown format with confidence markers (definite error, recommendation, or suggestion), per-error explanations, and a fully corrected version. It is context-aware, relaxing rules for informal writing, code comments, brand names, and intentional stylistic choices to avoid over-correction.

It is aimed at anyone writing Korean who wants quality assurance: authors reviewing documents, writers wanting real-time correction, developers checking Korean comments or docs, learners studying grammar with explanations, and teams ensuring official-document quality. Bundled before/after examples and two reference files make it usable both as a corrector and as a teaching aid.