I built Lexicon, a free, open-source desktop writing assistant. Clean grammar checking and text editing without sending your private drafts to cloud servers or paying monthly subscriptions. A rich editor includes LaTeX math, structured tables, code blocks, and clean PDF/Markdown exports. The app offers proofreading and 15 local text tools (Rewrite, Concise, Tone shifts, Summaries, Tables). It's completely free and open-source under the MIT license.

How did GPT-5.6 change the ambition or scope of what you shipped?

Helped me ideate a lot and gave me great suggestions on the UI/UX side of things. The biggest thing GPT 5.6 helped me with was building the Tauri app and GitHub releases. Before GPT 5.6 it was just a locally run app on a local host, but after GPT 5.6 I was able to create it as a desktop app, and then it helped me create a way to download the app itself via Github Release.

Hey Product Hunt! 👋

I'm the creator of Lexicon.

I built Lexicon because I wanted a clean desktop writing workspace that handles proofreading and AI transformations without sending private documents to cloud servers, requiring account logins, or asking for monthly subscriptions.

Why Lexicon is different:

100% Offline & Private: Zero cloud dependencies, zero telemetry, and zero accounts. Everything stays on your machine.
Local Proofreading: Fast grammar, punctuation, and spellchecking powered by a local LanguageTool engine.
15 On-Device AI Tools: Rewrite, Concise, 9 distinct Tone adjustments, Summarize, and Table generation running via local GGUF models (llama.cpp) or your own local Ollama server.
Rich Workspace: Includes focus mode, LaTeX math rendering, structured tables, code blocks, and clean PDF/Markdown exports.

The app is completely free and open-source (MIT licensed) with pre-packaged desktop installers for Windows (.exe) and macOS (.dmg).

I’d love to hear your thoughts, feedback, or any features you'd like to see next! Thanks for checking out Lexicon! 🚀

GitHub: https://github.com/AashishH15/Lexicon