Ritemark is a free, open-source Markdown editor for Mac and Windows that turns a folder on your computer into a workspace where ChatGPT or Claude work with you. You write in plain Markdown files with a visual editor, and the AI reads, writes and edits the same files when you ask in plain words. ChatGPT works with any account; Claude needs a paid plan. Teams use it for proposals, reports, training material and project documents: each project is one folder with its own conversations, instructions and task board, and the AI plans first and waits for your approval. It has tables with formulas, comments you can send to the AI, Mermaid and draw.io diagrams, and export to Word, PDF and Google Docs. Files stay on your computer as plain Markdown. MIT licensed.
