Redline

About

Visual design review, source-aware. Capture in the browser, ship a clean
  bundle to your AI agent.

  Redline turns any web page into a markup canvas. Click the toolbar icon to
  inject it into the current tab — then edit text inline, drag/resize/hide
  elements, change link targets (href), draw region annotations, paste
  screenshots, and leave notes. When you're done, hit Save and Redline downloads
   a single ZIP containing:

  • session.json — structured edits, annotations, and notes (with stable CSS
  selectors so an agent can patch the source HTML)
  • session.md — a human-readable Markdown summary
  • All your screenshot attachments as separate image files

  Hand the ZIP to Claude Code, Codex, OpenClaw, Hermes, or any agent that can
  read files. They read the JSON, apply the edits to source, and ship.


  WHO USES IT

  • Designers reviewing AI-generated landing pages, decks, and HTML reports
  • Engineers self-reviewing their own pages before merging agent output
  • PMs / founders writing spec changes against a live staging URL
  • Anyone giving feedback on a deck, report, or web app


  WHY REDLINE (vs. screenshots, Loom, or "tighten this here")

  • Edits, not just descriptions. Change "Subscribe" to "Get started" by
  actually typing it — the JSON records both before and after.
  • Source-mappable. Every edit ships with a stable CSS selector + content hash,
   so an agent can apply changes to the source repo directly even if the file
  regenerated.
  • AI-native output. The schema is documented and stable. The companion Claude
  Code skill (open source) reads the ZIP and patches your HTML automatically.
  • No account, no backend, no telemetry. Everything happens in your browser.
  Output is a ZIP you control.


  THREE CORE SCENARIOS

  • HTML slide decks — Reveal.js, deck-stage, plain HTML slides. Redline detects
   each slide and tags every change with its slide number.
  • HTML reports & docs — RFCs, white papers, design briefs. Annotate sections,
  mark paragraphs.
  • HTML landing pages & web apps — Edit copy, move elements, draw region notes,
   paste reference screenshots.


  POWER-USER MODE

  If you're a developer working on local files (file:// or localhost), enable
  "Write to local folder" in Settings (right-click the toolbar icon → Options)
  to write feedback straight into your project's ~/.redline/sessions/ folder
  using the FileSystem Access API. Skip the ZIP step entirely.


  WHAT IT DOES NOT DO

  • No telemetry, no analytics, no servers. See privacy policy.
  • Cannot inject into chrome:// pages, the Chrome Web Store, or other
  extensions' pages (browser security, not a Redline limitation).
  • Cross-origin iframes need to be triggered separately.


  OPEN SOURCE

  Source, issues, and roadmap: https://github.com/Dongke-X/redline (MIT)
  The companion Claude Code skill ships in the same repo — install it and skip
  the extension entirely if all you ever review is local AI-generated HTML.