gstack/SKILL.md

---
name: gstack
version: 1.1.0
description: |
  Fast headless browser for QA testing and site dogfooding. Navigate any URL, interact with
  elements, verify page state, diff before/after actions, take annotated screenshots, check
  responsive layouts, test forms and uploads, handle dialogs, and assert element states.
  ~100ms per command. Use when you need to test a feature, verify a deployment, dogfood a
  user flow, or file a bug with evidence.
allowed-tools:
  - Bash
  - Read
  - AskUserQuestion

---
<!-- AUTO-GENERATED from SKILL.md.tmpl — do not edit directly -->
<!-- Regenerate: bun run gen:skill-docs -->

## Update Check (run first)

```bash
_UPD=$(~/.claude/skills/gstack/bin/gstack-update-check 2>/dev/null || .claude/skills/gstack/bin/gstack-update-check 2>/dev/null || true)
[ -n "$_UPD" ] && echo "$_UPD" || true
```

If output shows `UPGRADE_AVAILABLE <old> <new>`: read `~/.claude/skills/gstack/gstack-upgrade/SKILL.md` and follow the "Inline upgrade flow" (AskUserQuestion → upgrade if yes, `touch ~/.gstack/last-update-check` if no). If `JUST_UPGRADED <from> <to>`: tell user "Running gstack v{to} (just updated!)" and continue.

# gstack browse: QA Testing & Dogfooding

Persistent headless Chromium. First call auto-starts (~3s), then ~100-200ms per command.
Auto-shuts down after 30 min idle. State persists between calls (cookies, tabs, sessions).

## SETUP (run this check BEFORE any browse command)

```bash
_ROOT=$(git rev-parse --show-toplevel 2>/dev/null)
B=""
[ -n "$_ROOT" ] && [ -x "$_ROOT/.claude/skills/gstack/browse/dist/browse" ] && B="$_ROOT/.claude/skills/gstack/browse/dist/browse"
[ -z "$B" ] && B=~/.claude/skills/gstack/browse/dist/browse
if [ -x "$B" ]; then
  echo "READY: $B"
else
  echo "NEEDS_SETUP"
fi
```

If `NEEDS_SETUP`:
1. Tell the user: "gstack browse needs a one-time build (~10 seconds). OK to proceed?" Then STOP and wait.
2. Run: `cd <SKILL_DIR> && ./setup`
3. If `bun` is not installed: `curl -fsSL https://bun.sh/install | bash`

## IMPORTANT

- Use the compiled binary via Bash: `$B <command>`
- NEVER use `mcp__claude-in-chrome__*` tools. They are slow and unreliable.
- Browser persists between calls — cookies, login sessions, and tabs carry over.
- Dialogs (alert/confirm/prompt) are auto-accepted by default — no browser lockup.

## QA Workflows

### Test a user flow (login, signup, checkout, etc.)

```bash
# 1. Go to the page
$B goto https://app.example.com/login

# 2. See what's interactive
$B snapshot -i

# 3. Fill the form using refs
$B fill @e3 "test@example.com"
$B fill @e4 "password123"
$B click @e5

# 4. Verify it worked
$B snapshot -D              # diff shows what changed after clicking
$B is visible ".dashboard"  # assert the dashboard appeared
$B screenshot /tmp/after-login.png
```

### Verify a deployment / check prod

```bash
$B goto https://yourapp.com
$B text                          # read the page — does it load?
$B console                       # any JS errors?
$B network                       # any failed requests?
$B js "document.title"           # correct title?
$B is visible ".hero-section"    # key elements present?
$B screenshot /tmp/prod-check.png
```

### Dogfood a feature end-to-end

```bash
# Navigate to the feature
$B goto https://app.example.com/new-feature

# Take annotated screenshot — shows every interactive element with labels
$B snapshot -i -a -o /tmp/feature-annotated.png

# Find ALL clickable things (including divs with cursor:pointer)
$B snapshot -C

# Walk through the flow
$B snapshot -i          # baseline
$B click @e3            # interact
$B snapshot -D          # what changed? (unified diff)

# Check element states
$B is visible ".success-toast"
$B is enabled "#next-step-btn"
$B is checked "#agree-checkbox"

# Check console for errors after interactions
$B console
```

### Test responsive layouts

```bash
# Quick: 3 screenshots at mobile/tablet/desktop
$B goto https://yourapp.com
$B responsive /tmp/layout

# Manual: specific viewport
$B viewport 375x812     # iPhone
$B screenshot /tmp/mobile.png
$B viewport 1440x900    # Desktop
$B screenshot /tmp/desktop.png
```

### Test file upload

```bash
$B goto https://app.example.com/upload
$B snapshot -i
$B upload @e3 /path/to/test-file.pdf
$B is visible ".upload-success"
$B screenshot /tmp/upload-result.png
```

### Test forms with validation

```bash
$B goto https://app.example.com/form
$B snapshot -i

# Submit empty — check validation errors appear
$B click @e10                        # submit button
$B snapshot -D                       # diff shows error messages appeared
$B is visible ".error-message"

# Fill and resubmit
$B fill @e3 "valid input"
$B click @e10
$B snapshot -D                       # diff shows errors gone, success state
```

### Test dialogs (delete confirmations, prompts)

```bash
# Set up dialog handling BEFORE triggering
$B dialog-accept              # will auto-accept next alert/confirm
$B click "#delete-button"     # triggers confirmation dialog
$B dialog                     # see what dialog appeared
$B snapshot -D                # verify the item was deleted

# For prompts that need input
$B dialog-accept "my answer"  # accept with text
$B click "#rename-button"     # triggers prompt
```

### Test authenticated pages (import real browser cookies)

```bash
# Import cookies from your real browser (opens interactive picker)
$B cookie-import-browser

# Or import a specific domain directly
$B cookie-import-browser comet --domain .github.com

# Now test authenticated pages
$B goto https://github.com/settings/profile
$B snapshot -i
$B screenshot /tmp/github-profile.png
```

### Compare two pages / environments

```bash
$B diff https://staging.app.com https://prod.app.com
```

### Multi-step chain (efficient for long flows)

```bash
echo '[
  ["goto","https://app.example.com"],
  ["snapshot","-i"],
  ["fill","@e3","test@test.com"],
  ["fill","@e4","password"],
  ["click","@e5"],
  ["snapshot","-D"],
  ["screenshot","/tmp/result.png"]
]' | $B chain
```

## Quick Assertion Patterns

```bash
# Element exists and is visible
$B is visible ".modal"

# Button is enabled/disabled
$B is enabled "#submit-btn"
$B is disabled "#submit-btn"

# Checkbox state
$B is checked "#agree"

# Input is editable
$B is editable "#name-field"

# Element has focus
$B is focused "#search-input"

# Page contains text
$B js "document.body.textContent.includes('Success')"

# Element count
$B js "document.querySelectorAll('.list-item').length"

# Specific attribute value
$B attrs "#logo"    # returns all attributes as JSON

# CSS property
$B css ".button" "background-color"
```

## Snapshot System

The snapshot is your primary tool for understanding and interacting with pages.

```
-i        --interactive           Interactive elements only (buttons, links, inputs) with @e refs
-c        --compact               Compact (no empty structural nodes)
-d <N>    --depth                 Limit tree depth (0 = root only, default: unlimited)
-s <sel>  --selector              Scope to CSS selector
-D        --diff                  Unified diff against previous snapshot (first call stores baseline)
-a        --annotate              Annotated screenshot with red overlay boxes and ref labels
-o <path> --output                Output path for annotated screenshot (default: /tmp/browse-annotated.png)
-C        --cursor-interactive    Cursor-interactive elements (@c refs — divs with pointer, onclick)
```

All flags can be combined freely. `-o` only applies when `-a` is also used.
Example: `$B snapshot -i -a -C -o /tmp/annotated.png`

**Ref numbering:** @e refs are assigned sequentially (@e1, @e2, ...) in tree order.
@c refs from `-C` are numbered separately (@c1, @c2, ...).

After snapshot, use @refs as selectors in any command:
```bash
$B click @e3       $B fill @e4 "value"     $B hover @e1
$B html @e2        $B css @e5 "color"      $B attrs @e6
$B click @c1       # cursor-interactive ref (from -C)
```

**Output format:** indented accessibility tree with @ref IDs, one element per line.
```
  @e1 [heading] "Welcome" [level=1]
  @e2 [textbox] "Email"
  @e3 [button] "Submit"
```

Refs are invalidated on navigation — run `snapshot` again after `goto`.

## Command Reference

### Navigation
| Command | Description |
|---------|-------------|
| `back` | History back |
| `forward` | History forward |
| `goto <url>` | Navigate to URL |
| `reload` | Reload page |
| `url` | Print current URL |

### Reading
| Command | Description |
|---------|-------------|
| `accessibility` | Full ARIA tree |
| `forms` | Form fields as JSON |
| `html [selector]` | innerHTML of selector (throws if not found), or full page HTML if no selector given |
| `links` | All links as "text → href" |
| `text` | Cleaned page text |

### Interaction
| Command | Description |
|---------|-------------|
| `click <sel>` | Click element |
| `cookie <name>=<value>` | Set cookie on current page domain |
| `cookie-import <json>` | Import cookies from JSON file |
| `cookie-import-browser [browser] [--domain d]` | Import cookies from Comet, Chrome, Arc, Brave, or Edge (opens picker, or use --domain for direct import) |
| `dialog-accept [text]` | Auto-accept next alert/confirm/prompt. Optional text is sent as the prompt response |
| `dialog-dismiss` | Auto-dismiss next dialog |
| `fill <sel> <val>` | Fill input |
| `header <name>:<value>` | Set custom request header (colon-separated, sensitive values auto-redacted) |
| `hover <sel>` | Hover element |
| `press <key>` | Press key — Enter, Tab, Escape, ArrowUp/Down/Left/Right, Backspace, Delete, Home, End, PageUp, PageDown, or modifiers like Shift+Enter |
| `scroll [sel]` | Scroll element into view, or scroll to page bottom if no selector |
| `select <sel> <val>` | Select dropdown option by value, label, or visible text |
| `type <text>` | Type into focused element |
| `upload <sel> <file> [file2...]` | Upload file(s) |
| `useragent <string>` | Set user agent |
| `viewport <WxH>` | Set viewport size |
| `wait <sel|--networkidle|--load>` | Wait for element, network idle, or page load (timeout: 15s) |

### Inspection
| Command | Description |
|---------|-------------|
| `attrs <sel|@ref>` | Element attributes as JSON |
| `console [--clear|--errors]` | Console messages (--errors filters to error/warning) |
| `cookies` | All cookies as JSON |
| `css <sel> <prop>` | Computed CSS value |
| `dialog [--clear]` | Dialog messages |
| `eval <file>` | Run JavaScript from file and return result as string (path must be under /tmp or cwd) |
| `is <prop> <sel>` | State check (visible/hidden/enabled/disabled/checked/editable/focused) |
| `js <expr>` | Run JavaScript expression and return result as string |
| `network [--clear]` | Network requests |
| `perf` | Page load timings |
| `storage [set k v]` | Read all localStorage + sessionStorage as JSON, or set <key> <value> to write localStorage |

### Visual
| Command | Description |
|---------|-------------|
| `diff <url1> <url2>` | Text diff between pages |
| `pdf [path]` | Save as PDF |
| `responsive [prefix]` | Screenshots at mobile (375x812), tablet (768x1024), desktop (1280x720). Saves as {prefix}-mobile.png etc. |
| `screenshot [path]` | Save screenshot |

### Snapshot
| Command | Description |
|---------|-------------|
| `snapshot [flags]` | Accessibility tree with @e refs for element selection. Flags: -i interactive only, -c compact, -d N depth limit, -s sel scope, -D diff vs previous, -a annotated screenshot, -o path output, -C cursor-interactive @c refs |

### Meta
| Command | Description |
|---------|-------------|
| `chain` | Run commands from JSON stdin. Format: [["cmd","arg1",...],...] |

### Tabs
| Command | Description |
|---------|-------------|
| `closetab [id]` | Close tab |
| `newtab [url]` | Open new tab |
| `tab <id>` | Switch to tab |
| `tabs` | List open tabs |

### Server
| Command | Description |
|---------|-------------|
| `restart` | Restart server |
| `status` | Health check |
| `stop` | Shutdown server |

## Tips

1. **Navigate once, query many times.** `goto` loads the page; then `text`, `js`, `screenshot` all hit the loaded page instantly.
2. **Use `snapshot -i` first.** See all interactive elements, then click/fill by ref. No CSS selector guessing.
3. **Use `snapshot -D` to verify.** Baseline → action → diff. See exactly what changed.
4. **Use `is` for assertions.** `is visible .modal` is faster and more reliable than parsing page text.
5. **Use `snapshot -a` for evidence.** Annotated screenshots are great for bug reports.
6. **Use `snapshot -C` for tricky UIs.** Finds clickable divs that the accessibility tree misses.
7. **Check `console` after actions.** Catch JS errors that don't surface visually.
8. **Use `chain` for long flows.** Single command, no per-step CLI overhead.