Md Redline

md-redline

[](https://www.npmjs.com/package/md-redline)

Inline review comments for markdown specs, prompts, and design docs.

Highlight text in a rendered document, leave comments, and your AI agent can read and address them directly. Comments are stored as invisible HTML markers in the `.md` file itself. No sidecar files, no database, no external service. The markdown file stays the source of truth.

With the built-in MCP server, review runs in both directions. Your agent can request your review mid-task and pause until you send your feedback, or review a doc you wrote and leave anchored comments for you. Either way: no copy-paste, no context switching.


**See the full review workflow in 30 seconds:**

https://github.com/user-attachments/assets/3a2bf20a-d4a0-403c-b023-e877130fd959

Works with [Claude Code](https://claude.com/claude-code), Claude Desktop, [Codex CLI](https://github.com/openai/codex), [Gemini CLI](https://github.com/google-gemini/gemini-cli), and any other MCP client that supports stdio servers. As Sean Grove argues in [specs are the new code](https://www.youtube.com/watch?v=8rABwKRsec4), specs are becoming the primary unit of work in agentic development. `mdr` gives that workflow review tooling closer to code review.

Quick start

Prerequisite: Node 20 or newer.

npx md-redline /path/to/spec.md

This starts the local app if needed and opens it in your browser.

Or install globally:

npm install -g md-redline
mdr /path/to/spec.md        # Open a file
mdr /path/to/dir             # Open a directory
mdr --stop                   # Stop the running server

`md-redline` also works as an alias for `mdr`.

That gives you the viewer and commenting. The agent integration (reviews in both directions, anchored qu