Getting Started

From install to your first review.

Loupe is a local desktop app for reviewing and creating code and documents with Claude Code or Codex. This guide takes you from download to your first review in a few minutes.

What you need

  • A supported platform: macOS (Apple Silicon) or Linux (x86_64). Windows is planned.
  • A local git repository to review: any branch on your machine works; nothing needs to be pushed anywhere.
  • A coding agent: Claude Code and/or Codex, installed separately. The agent is the core of Loupe: it makes changes, answers questions, and applies fixes right beside your work, so have one available before you start.

Install

Grab the build for your platform from the Downloads page.

  • macOS: open the .dmg and drag Loupe into Applications. Builds are signed with an Apple Developer ID and notarized, so they open without a Gatekeeper warning.
  • Linux: make the .AppImage executable (chmod +x Loupe-*.AppImage) and run it.

Loupe checks for updates automatically. You can switch between the Stable and Nightly update channels in Settings.

First run

  1. Create or open a workspace. A workspace groups the repositories you want to work with together.
  2. Add a repository. Point Loupe at a local repo on your machine.
  3. Choose what to review. Pick a base branch and the branch you want to look at.
  4. Open the review view and start diffing.
No account needed. Loupe works with your local repositories out of the box. From the landing screen you can open an existing branch or start new work.
Loupe's workspace landing screen: Create a Workspace with Start New Work, Open Existing Branch, and Review a PR, alongside a list of recent workspaces

The core loop

Whether the agent wrote the change or you did, Loupe keeps you in a tight loop that never leaves the diff:

Loupe is agent-first by design. You make changes by directing the agent, whether in chat or through comments on the diff, rather than hand-editing files. Coming from an IDE, that's the shift: you steer, and the agent makes the edit.
  1. Browse the diff. Files in a sidebar, syntax-highlighted changes in the main panel.
  2. Select a line or range and choose an intent:
    • Ask: the agent explains why the code is the way it is.
    • Plan: the agent drafts a change you can apply or dismiss, without touching your files yet.
    • Fix: the agent edits the code directly, and the diff refreshes live.
  3. Iterate until you're satisfied, resolving comments as you go.
Reviewing documents? Markdown files render as formatted pages instead of raw diffs. Read them the way they'll look, and comment by selecting a word or passage rather than a line number. Great for specs, design docs, and content reviews, no code required.

Working with GitHub optional

Loupe works entirely with your local repositories; GitHub is never required. When you do connect it, it adds two things:

  • Another way to start a review. Paste a pull-request URL, or browse your open PRs, and Loupe opens the PR as a diff: the same review surface, backed by a PR instead of a local branch.
  • Two-way comment sync. Pull a PR's existing review comments into Loupe, or publish your local comments back to the PR. Only the reviewer needs Loupe; teammates still see everything on GitHub.

To use these, install the GitHub CLI (gh) and sign in from the account menu. Loupe shows a device code to enter at github.com/login/device.

Settings worth knowing

  • Agent: choose the agent type (Claude Code or Codex), the permission mode (Default, Auto, or Bypass), and an optional model override.
  • Update channel: Stable for released versions, Nightly for early builds from the latest code.
  • Telemetry: off by default. Choose off, errors only, or all. Logs are always written locally and never leave your machine unless you choose to share a diagnostic bundle.
  • Review pane & git: file-tree mode, auto-refresh on file changes, and your preferred branch-update strategy (rebase or merge).

Ready to go? Download Loupe and open your first branch.