A Markdown viewer for what Claude writes.
Plans, reports, specs and runbooks — in the mode that fits: Reading, Plan or Interactive.

Claude produces a lot of Markdown, and every tool treats it as plain text. An implementation plan is not an article — it has phases, tasks, blockers and open questions. A 4,000-word report shouldn't be read in a terminal. A runbook needs ticking, searching and folding.

Marko reads the file the way you're going to use it, and stays out of the way of the file itself: Markdown remains the source of truth, and Marko is a lens on it.

Marko picks the mode from the file (front matter, name, content) and remembers your choice. Tick tasks in Plan mode and Copy Updated Markdown hands you the file with the [x] marks written in.

Pick one — they share the same viewer.

Claude Code plugin (recommended)

/plugin marketplace add baberjaved/marko-md
/plugin install marko@marko-md

Adds /marko:view <file>, a marko command on Claude's PATH, and hooks that surface plans and reports the moment Claude writes them.

npm

npm install -g marko-md      # then: marko open plan.md
npx marko-md open plan.md    # no install

Mac and Windows apps — download from Releases (Marko-x.y.z.dmg / Marko-x.y.z-win-x64.zip), or build in seconds:

app/mac/build.sh --install --default          # macOS: Command Line Tools only
.\app\windows\build.ps1 -Install -Default     # Windows: .NET 8 SDK

Both are ~1–2 MB, open .md files by double-click and reload when the file changes. Mac details · Windows details

Nothing at all — grab marko-viewer.html, open it in a browser, drag a file in.

marko serve            # leave running in a second terminal

Every plan or report Claude writes now appears in that tab and updates as Claude edits it. Review, tick, copy the ticks back, tell Claude what to change. Or ask for a file directly:

/marko:view plans/auth-migration.md

flowchart LR
  A[Claude Code writes<br>plans/auth.md] -->|PostToolUse hook| H[marko hook]
  H -->|live tab open| L[refresh in place]
  H -->|Marko.app installed| M[open in the app]
  H -->|otherwise| N["ready to review with /marko:view"]

Config lives in .claude/marko.json (what to watch, which mode per folder, whether to auto-open). Full details in the Installation & Usage Guide — which is itself a Marko document.

• Private. No accounts, no telemetry, no uploads. marko serve binds to localhost only. The only network requests are three libraries from cdnjs, and the desktop apps bundle those.
• Native look. System fonts (San Francisco, New York and SF Mono on a Mac), light and dark, keyboard-first: 1 2 3 modes, j k sections, / search, Esc back.
• Claude's dialect. Front matter, task lists, **Status:** lines, callouts (> **Note:** and > [!TIP]), Mermaid diagrams, 🤖 Generated with Claude Code footers — all understood.
• Zero dependencies. The CLI is one Node file. The viewer is one HTML file. The apps are one Swift file and one C# file.

• Diff view between two revisions of the same document
• Save ticks straight back to the file from the apps
• Quick Look extension for macOS
• Tabs, folder mode, annotations

Ideas and issues welcome — open one. If Marko is useful to you, a ⭐ helps others find it.

npm run build     # src/viewer.template.html + samples → viewer/marko.html, dist/marko-demo.html
npm test          # CLI, hooks, live server

Tagging vX.Y.Z builds the Mac DMG and Windows zip and publishes a GitHub Release automatically.

MIT © Baber Javed