Lexicon is a rich-text editor with grammar checking and AI writing tools (rewriting, tone shifting, and summarizing) that run entirely on your machine. No account, no API calls, and nothing uploaded. Grammar/spelling/punctuation checking runs through LanguageTool locally; the AI tools run through a small quantized model bundled with the app via llama.cpp, or your own Ollama server if you already run one. It's a desktop app installer for Windows and macOS on the releases page, with an in-app auto-updater.
Check it out: https://lexicon-writer.pages.dev/
MIT licensed. Repo: https://github.com/AashishH15/Lexicon
Please let me know what you think of the app!