# Halo App

> Drive and test the running Halo Electron debug renderer, or inspect an extension in an isolated browser using the Halo CLI.

- Skill: `tanishqkancharla/halo-app` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add tanishqkancharla/halo-app`
- Raw SKILL.md: https://api.skillmd.com/api/skills/tanishqkancharla/halo-app/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: tanishqkancharla (https://skillmd.com/u/tanishqkancharla)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/tanishqkancharla/halo-app

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# Halo app and browser control

Use `pnpm halo` from the repository root, or the installed `halo` command from a workspace. The CLI connects to the running Halo server. It does not build, launch, restart, or quit the app.

## Inspect Halo

```sh
pnpm halo status
pnpm halo app snapshot
pnpm halo app exec 'return await page.title()'
pnpm halo app exec 'await page.getByRole("button", { name: "New session", exact: true }).click()'
pnpm halo app screenshot
```

`halo app` targets the Halo renderer, not DevTools. It requires a development build with its debug port on `127.0.0.1:4445`. If the app is not running and the task calls for live testing, start `pnpm --filter @halo/desktop dev` in a long-running terminal.

## Test an extension independently

```sh
halo browser open http://127.0.0.1:3000/view/
halo browser exec <id> 'await page.getByRole("textbox", { name: "Your name" }).fill("Ada")'
halo browser snapshot <id>
halo browser screenshot <id>
halo browser close <id>
```

Each `open` returns a browser ID, URL, title, accessibility tree, and runtime errors. It creates a private browser with isolated state; open the same extension twice to test collaboration. The page survives commands, while JavaScript variables do not. Each `exec` receives a live Playwright `page` and captures console output and accessibility changes. Use `return` to report a result. `halo browser list` finds existing sessions.

Prefer accessible names, labels, and roles. Wait for the visible effect of an action before inspecting it. For longer scripts, pass `--file checks.js` or `--stdin` to either target's `exec` command. Screenshots return a workspace PNG path; read that file to inspect the actual layout.

Use private browser sessions for extension testing so the user's Halo navigation stays theirs. A hosted extension still shares its data through Tandem, so use a standalone preview with isolated data for test mutations. Close every browser opened for testing. Halo also closes them when the workspace changes or the app quits.

Use `halo browser --help` and `halo app --help` for command discovery. Output uses TOON by default; add `--json` when another command must parse it. Halo provisions Chromium once on first browser use; extensions do not need their own browser tooling installation.