Baby SWE

Agent Development Environment built with Electron + React + Zustand, running as an ACP client with swappable harnesses.

Installation

Quick Install (npm)

npx baby-swe

Or install globally:

npm install -g baby-swe
baby-swe

From Source

git clone https://github.com/langchain-ai/baby-swe.git
cd baby-swe
bun install
bun run dev

ACP-First Architecture

Baby SWE talks ACP and can switch harnesses at runtime from Settings (top-right cog).

• cursor harness (default): runs Cursor ACP via agent acp
• deepagents harness: runs Deepagents ACP via deepagents-acp

Harness selection is persisted in app settings.

Auth and Keys

Cursor Harness

• Uses your existing Cursor CLI auth session.
• Authenticate with agent login (or from Settings: Authenticate with Cursor CLI).
• Check status with agent status.
• No Baby SWE API keys required for this harness.

Deepagents Harness

• Uses your own model provider keys.
• Configure via .env or in-app /keys.
• At least one LLM key is required:
  • Anthropic (ANTHROPIC_API_KEY)
  • OpenAI (OPENAI_API_KEY)
  • Baseten (BASETEN_API_KEY, for Kimi)
• Optional web-search key:
  • Tavily (TAVILY_API_KEY)

Requirements

• Bun
• Cursor CLI (agent) for the Cursor harness

Development

bun install
bun run dev    # build + launch
bun run watch  # watch mode (main/renderer/css/electron)
bun run build  # production build to ./dist

Packaging

bun run pack       # unpacked app
bun run dist       # current platform
bun run dist:mac   # macOS (zip target)
bun run dist:win   # Windows (nsis + portable)
bun run dist:linux # Linux (AppImage + deb)

Artifacts are written to release/.

Features

• 5 workspaces with tiling layout
• Tile types: agent, terminal, source-control, file-viewer, diff-viewer
• ACP harness switching in Settings (cursor / deepagents)
• Cursor auth status + login from Settings
• Git branch + PR awareness, plus worktree support
• Tool-call streaming with inline outputs and approvals
• Modes: agent, yolo
• Session TODO tracking (write_todos)
• Thread persistence and /resume
• Manual context compaction (/compact)

Project Layout

src/
  main.ts            Electron main process + IPC + git/worktree + terminal PTY
  preload.ts         Secure renderer bridge APIs
  acp-client.ts      ACP JSON-RPC transport, harness command routing, auth helpers
  agent.ts           ACP session orchestration, streaming, approvals, compaction
  store.ts           Zustand app/session/workspace state
  commands/          Slash command registration and handlers
  memory/            AGENTS.md memory loading
  prompts/           Prompt templates + dynamic system prompt builder
  ui/                React app and components

Slash Commands

/help, /clear, /new, /tokens, /compact, /model, /keys, /resume, /remember

Optional ACP Command Overrides

For advanced setups you can override harness commands with env vars:

• Cursor ACP: BABY_SWE_ACP_COMMAND, BABY_SWE_ACP_ARGS
• Cursor CLI auth/status command: BABY_SWE_CURSOR_CLI_COMMAND
• Deepagents ACP: BABY_SWE_DEEPAGENTS_ACP_COMMAND, BABY_SWE_DEEPAGENTS_ACP_ARGS

Notes

• Use Bun only (no npm/yarn/pnpm).
• App settings/projects/threads are stored under Electron userData.
• On macOS this app pins userData to ~/Library/Application Support/Baby SWE.

License

MIT