#What Fold is

Fold is a lightweight, terminal-first IDE for macOS, built for one specific job: running several AI coding agents in parallel on the same project, and reviewing what they did.

It is an Electron desktop app. One window per project. No login, no cloud, no extensions, no language server.

#The problem it solves

If you run 2–6 agents at once — Claude Code and friends — you end up juggling Terminal.app tabs to watch them and a separate editor to check their work. Fold collapses that into one window:

• Terminals hold the main stage, not a bottom drawer
• A git diff is one keystroke away, so agent output is reviewable before it becomes a commit
• An editor good enough for quick manual edits between agent turns

#Pillars

Terminals are the main stage. Sessions are cheap to create, name, kill and split. Everything else in the app exists to support what's running in them.

Review, don't just run. The git panel exists so agent output is inspectable — see the diff, stage, commit, push — without leaving the app.

Boring, native-feeling speed. Instant launch. No LSP, no extensions, no cloud, no login. It should feel like a terminal, not like an IDE booting.

Minimal surface. Every dependency is sanctioned in the design docs. The UI chrome is vanilla TypeScript — no framework.

#The core loop

 open project folder
        │
        ▼
 spawn agent sessions ──────────────┐
        │                           │
        ▼                           │
 watch / steer agents               │  (split panes,
 in terminal panes                  │   session sidebar)
        │                           │
        ▼                           │
 review changes in git panel        │
 (diff per file)                    │
        │                           │
        ├── looks good ──► stage → commit → push
        │
        └── needs work ──► hand fix back to an agent, or
                           quick manual edit in the editor ──┘

#Inspirations, and their limits

cmux — the session sidebar and the parallel-agents workflow. Fold takes the multi-session model and skips the cloud and orchestration layers.

VS Code — the open-folder model, the layout grammar (activity bar / sidebar / editor / panel / status bar), and the Source Control panel. Fold takes the grammar; it is explicitly not trying to be VS Code.

#What Fold is not

• Not an extension host. There is no plugin API and no marketplace.
• Not a language server client. No autocomplete, no go-to-definition, no refactoring.
• Not a collaboration tool. Nothing leaves your machine.
• Not agent-specific. Fold does not read or write any agent's configuration; it runs your shell and gets out of the way.

#The guide

Elsewhere: Install and Release notes.