Baton
Baton app
Native floating launcher on macOS; app-style browser window elsewhere. Never steals focus. baton hud is only an alias.
Runtime instrument · v0.2.6 preview
Pass theruntime.
Baton is a loopback control plane for people and coding agents. Run the app, hot-reload it, boot the simulator, and keep the proof — without an IDE holding the mouse.
Workflow proof
The loop an IDE cannot share.
Baton launches and reports evidence. It does not tap the UI or judge a screenshot. Capture success means an image was written — you or the agent still have to look.
01
targets, devices, blockers
inspect_project
02
start from a copy if you asked
run_target / run_workflow
03
ready, not a sleep
wait_for
04
structured evidence
screenshot / read_logs
05
87ms on a 3,692-library Flutter app
hot_reloadFailed reloads return the compiler error, not “DevFS synchronization failed.” MCP cannot yet boot simulators — use baton boot "iPhone 17 Pro" or a device that is already running.
Framework support
Honest capabilities.
A Vite session does not claim Flutter’s stateful hot reload. The control panel greys the button; agents get a refusal instead of a silent no-op.
Flutter / Dart
Daemon protocol, DevTools, debug flags, screenshots
Next.js, Vite, Nuxt, Astro, Remix, Angular, CRA
HMR on save; Baton restarts the server when you ask
React Native / Expo
Fast Refresh; reload broadcast to Metro clients
Anything in launch.json or package.json
Kill and respawn, logs, session identity
Control surface
Same sessions. Three hands.
One daemon on loopback. The app, the CLI, and baton-mcp all authenticate with a token in ~/.baton/daemon.json (mode 0600).
CLI
baton list, run, reload --all, boot, doctor. Commands exit non-zero on failure.
MCP tools
Structured run, wait, logs, diagnose, network, proof. First tool call starts the daemon if needed.
ROI by team size
Modeled, not invented.
Hot reload in 87ms and restart in 359ms were measured on a production Flutter app. Time and token ranges below are scenarios you can argue with.
Installation
One machine. Then any client.
Install on the computer that actually runs the apps. Requires Node.js 24+. There is no App Store binary.
npm install -g github:kanumuri9593/Baton#v0.2.6 baton app
{
"mcpServers": {
"baton": { "command": "baton-mcp" }
}
}
npm install -g baton-run. Pin with github:kanumuri9593/Baton#v0.2.6. Full install, MCP, CLI, app, and troubleshooting →
Documentation
For people and agents.
Crawlers can start at llms.txt. Agents should prefer AGENTS.md.
Instruction set
Install, MCP tools, CLI fallback, safety, and the current MCP boot limitation.
Launch guide
First run, Flutter lab, proof matrices, workflows, OpenTelemetry tracing.
AGENTS.md
Tool list and the inspect → run → wait → evidence → reload loop.
App settings
Appearance, reduced motion, always-on-top, launch at login.
Feature requests
Tell us the missing control.
Adapters people have already asked for: Expo depth, Storybook, Tauri, Electron, Rails, Django, Phoenix, dotnet watch, Go with Air. A boot_device MCP tool is planned.