redline.dev / v0.1 / open source
The planning IDE for Claude Code
When Claude Code finishes planning, the plan opens in Redline instead of a terminal prompt. Mark it up with Word-style tracked changes and margin comments, ask questions, iterate through revisions — and approve it only when it’s right. Your markup flows back into the live session as structured feedback Claude Code acts on precisely.
Free & open source · Apache-2.0 · macOS-first, Windows & Linux build targets · Local-only.
Fig. 01 / A plan held for review in Redline
Redline — review the plan before Claude writes the code
Why
In a terminal, your only way to respond to a plan is to type one long message against a wall of text, in the terminal response window. There’s no way to point at a specific line, no way to attach a comment to the paragraph it’s about, and no record of what got addressed across rounds — and no version history..
Redline opens every Claude Code plan in a track-changes editor instead — mark it up the way a lawyer redlines a contract, and approve it only when it’s right. The cheapest place to catch a mistake is the plan.
Features
- Word-style track changes for plans. Edit the plan directly — insertions and deletions show as tracked marks — and every comment sits exactly where it belongs: on the paragraph, sentence, or word it’s about.
- The session waits for you. When Claude Code finishes a plan, Redline holds the session open while you review. Approve when it’s right, not when the terminal gets impatient.
- Ask vs Revise. Ask questions without changing a word of the plan, or send your full markup and get a new numbered version back — with an answer attached to every comment you made.
- Discussion forks. Open a side conversation on any comment, push back, and bring the outcome into your next round — or let Claude propose the edit directly in the document, with Accept and Reject in your hands.
- Revisions navigator. Browse every version of a plan, restore an earlier one, or export any of them as Markdown or Word.
> ⏸ plan mode on (shift+tab to cycle) · esc to interrupt ── plan intercepted by redline ──
How it works
protocol
- 01Intercept
Intercept — Redline installs a PreToolUse hook on ExitPlanMode. When Claude Code finishes planning, the plan is POSTed to a local daemon and the session is held open while you review.
- 02Redline
Redline — The plan opens in a track-changes editor. Type edits directly into the text, and attach edits, feedback, questions, and structural changes exactly where they apply.
- 03Submit
Submit — Two modes: Ask sends questions only and the plan body comes back unchanged. Revise sends your full markup and drives a new revision.
- 04Resolve
Resolve — The next revision arrives with a resolution attached to every comment. Accept each one, or reopen it for the next round. Approve when it's right.
Modes
interception
Every plan blocks and waits for your review. Nothing proceeds until you approve or send revisions.
block & review
A decision window with a countdown. Claim it to review in full, or let it auto-approve and stay in flow.
countdown · auto-approve
Kill switch. Everything passes straight through, nothing captured.
full passthrough
Switch from the header or the tray icon. Redline sits in your tray and shows pending reviews at a glance.
A full workspace
capabilities
Real PTY-backed shells and a sidebar file tree with a fast read-only viewer — run Claude Code inside Redline and review the plan next to the code it touches.
xterm · pty · file tree
Open a read-only side conversation with Claude on any comment. Ask follow-ups about the plan without disturbing the held session.
fork agent · read-only
Browse every version of a plan, restore an earlier one, and export any revision as clean Markdown or DOCX.
v1…vN · md · docx
Review state persists through crashes and restarts — the live document in Yjs + IndexedDB, sessions and comments in SQLite.
yjs · sqlite
Redline installs its own Claude Code hook and skill on first run. Both are plain files you can inspect, and the hook can be paused from inside the app.
hook · skill
Why Redline
rationale
Redline was built by a lawyer who wanted to mark up plans the way lawyers redline contracts: tracked changes, margin comments, and nothing accepted until it’s resolved. The underlying bet is that the cheapest place to catch a mistake is the plan.
- vs. approving in the terminal
- In the terminal, your only response to a plan is one undifferentiated prose message against a wall of text. In Redline you comment on §B.p2, not on scrollback.
- vs. just reading the plan
- You edit it directly. Insertions and deletions appear as tracked marks and return to the agent verbatim.
- vs. accept/undo tools
- Nothing happens until you approve. Every comment gets an explicit resolution in the next revision, and nothing is accepted until you accept it.
- Local-first
- No cloud, no account, no telemetry. The daemon listens on 127.0.0.1 and your work stays on your machine.
Install
build from source
No prebuilt binaries yet — Redline is an early release (v0.1) and builds from source. macOS is the primary development platform; Windows and Linux are build targets.
prerequisites
- ▸ Claude Code
- ▸ Node.js and npm
- ▸ Rust (stable, via rustup)
- ▸ Tauri 2 system dependencies
On first launch, Redline offers a one-click install of its Claude Code hook and plan-revision skill. Then run claude in the embedded terminal and plan as usual.
git clone https://github.com/sersiousSenpai/redline.git cd redline npm install npm run tauri dev
/repo
Redline is open source.
Read the code, file issues, send patches. No telemetry to audit because there isn’t any.
Tauri 2: a React 19 frontend and a Rust backend embedding an axum daemon, a SQLite session store, and PTY shells. Apache-2.0 licensed — your first pull request triggers a quick CLA.
The cheapest place to catch a mistake is the diff the plan.
Free & open source · Apache-2.0 · macOS-first · Local-only.