Open markdown files in a formatted viewer panel with live reload. Use when you need to display plans, documentation, or notes alongside the terminal with rich rendering (headings, code blocks, tables, lists).

Markdown Viewer with cmux Write a .md file, open it in a panel, and the panel re renders whenever the file changes on disk. Use it for agent plans and task lists alongside the terminal, documentation and changelogs while working, and notes another process updates progressively. Relative paths resolve against the caller's cwd and ~ expands; the resolved absolute path comes back in the output. Agent usage Write the full plan file first, then open it, so the panel never shows a partially written file. After that, overwrite or append freely: each write triggers a re render, and atomic replacement (editor saves, sed i , VS Code) is handled. To instruct coding agents in a project, add to its AGENTS.md : Rendering Headings h1 h6 (dividers on h1/h2), fenced code blocks in monospace, inline code with a highlighted background, tables with alternating row colors, nested ordered and unordered lists, blockquotes with a left border, bold/italic/strikethrough, clickable links, horizontal rules, and inline images. Light and dark mode both supported. Deep dive references Reference When to Use [references/commands.md](references/commands.md) Full command syntax, options, output shape, panel behavior [references/live reload.md](references/live reload.md) File watching, atomic writes, unavailable file state, performance

cmux-markdown