MarkSight is a free, open source markdown workspace. Write markdown on the left and see it rendered live on the right, with a formatting toolbar, keyboard shortcuts, a document outline, and light/dark themes. Everything stays local in your browser. Turn any document into an agent Skill in one click: add a name and description, attach bundled files, and export a ready-to-use SKILL.md folder or .skill bundle for Claude and other AI agents. Export documents to HTML, PDF, or raw Markdown.