---
name: agent-browser
description: Automates browser and Electron app interactions for user-flow validation.
---

# Browser Automation with agent-browser

## One-time setup (fresh machines)

If you see an error like "Executable doesn't exist ... chrome-headless-shell", install the bundled Chromium:

```bash
agent-browser install
```

## Quick start

```bash
agent-browser open <url>        # Navigate to page
agent-browser snapshot -i       # Get interactive elements with refs
agent-browser click @e1         # Click element by ref
agent-browser fill @e2 "text"   # Fill input by ref
agent-browser close             # Close browser
```

## Core workflow

1. Navigate: `agent-browser open <url>`
2. Snapshot: `agent-browser snapshot -i` (returns elements with refs like `@e1`, `@e2`)
3. Interact using refs from the snapshot
4. Re-snapshot after navigation or significant DOM changes

## Command chaining

Commands can be chained with `&&` in a single shell invocation. The browser persists between commands via a background daemon, so chaining is safe and more efficient than separate calls.

```bash
# Chain open + wait + snapshot in one call
agent-browser open https://example.com && agent-browser wait --load networkidle && agent-browser snapshot -i

# Chain multiple interactions
agent-browser fill @e1 "user@example.com" && agent-browser fill @e2 "password123" && agent-browser click @e3

# Navigate and capture
agent-browser open https://example.com && agent-browser wait --load networkidle && agent-browser screenshot page.png
```

**When to chain:** Use `&&` when you don't need to read the output of an intermediate command before proceeding (e.g., open + wait + screenshot). Run commands separately when you need to parse the output first (e.g., snapshot to discover refs, then interact using those refs).

## Commands

### Navigation

```bash
agent-browser open <url>      # Navigate to URL (aliases: goto, navigate)
                              # Supports: https://, http://, file://, about:, data://
                              # Auto-prepends https:// if no protocol given
agent-browser back            # Go back
agent-browser forward         # Go forward
agent-browser reload          # Reload page
agent-browser close           # Close browser (aliases: quit, exit)
agent-browser connect 9222    # Connect to browser via CDP port
```

### Snapshot (page analysis)

```bash
agent-browser snapshot            # Full accessibility tree
agent-browser snapshot -i         # Interactive elements only (recommended)
agent-browser snapshot -i -C      # Include cursor-interactive elements (divs with onclick, cursor:pointer)
agent-browser snapshot -c         # Compact output
agent-browser snapshot -d 3       # Limit depth to 3
agent-browser snapshot -s "#main" # Scope to CSS selector
```

### Interactions (use @refs from snapshot)

```bash
agent-browser click @e1           # Click
agent-browser click @e1 --new-tab # Click and open in new tab
agent-browser dblclick @e1        # Double-click
agent-browser focus @e1           # Focus element
agent-browser fill @e2 "text"     # Clear and type
agent-browser type @e2 "text"     # Type without clearing
agent-browser press Enter         # Press key (alias: key)
agent-browser press Control+a     # Key combination
agent-browser keydown Shift       # Hold key down
agent-browser keyup Shift         # Release key
agent-browser hover @e1           # Hover
agent-browser check @e1           # Check checkbox
agent-browser uncheck @e1         # Uncheck checkbox
agent-browser select @e1 "value"  # Select dropdown option
agent-browser select @e1 "a" "b"  # Select multiple options
agent-browser scroll down 500     # Scroll page (default: down 300px)
agent-browser scrollintoview @e1  # Scroll element into view (alias: scrollinto)
agent-browser drag @e1 @e2        # Drag and drop
agent-browser upload @e1 file.pdf # Upload files
```

### Get information

```bash
agent-browser get text @e1        # Get element text
agent-browser get text body > page.txt  # Get all page text to file
agent-browser get html @e1        # Get innerHTML
agent-browser get value @e1       # Get input value
agent-browser get attr @e1 href   # Get attribute
agent-browser get title           # Get page title
agent-browser get url             # Get current URL
agent-browser get count ".item"   # Count matching elements
agent-browser get box @e1         # Get bounding box
agent-browser get styles @e1      # Get computed styles (font, color, bg, etc.)
```

### Check state

```bash
agent-browser is visible @e1      # Check if visible
agent-browser is enabled @e1      # Check if enabled
agent-browser is checked @e1      # Check if checked
```

### Screenshots & PDF

```bash
agent-browser screenshot              # Save to a temporary directory
agent-browser screenshot path.png     # Save to a specific path
agent-browser screenshot --full       # Full page screenshot
agent-browser screenshot --annotate   # Annotated screenshot with numbered element labels
agent-browser pdf output.pdf          # Save as PDF
```

### Video recording

```bash
agent-browser record start ./demo.webm    # Start recording (uses current URL + state)
agent-browser click @e1                   # Perform actions
agent-browser record stop                 # Stop and save video
agent-browser record restart ./take2.webm # Stop current + start new recording
```

Recording creates a fresh context but preserves cookies/storage from your session. If no URL is provided, it
automatically returns to your current page. For smooth demos, explore first, then start recording.

### Diff (compare page states)

```bash
agent-browser diff snapshot                          # Compare current vs last snapshot
agent-browser diff snapshot --baseline before.txt    # Compare current vs saved file
agent-browser diff screenshot --baseline before.png  # Visual pixel diff
agent-browser diff url <url1> <url2>                 # Compare two pages
agent-browser diff url <url1> <url2> --wait-until networkidle  # Custom wait strategy
agent-browser diff url <url1> <url2> --selector "#main"  # Scope to element
```

Use `diff snapshot` after performing an action to verify it had the intended effect. This compares the current accessibility tree against the last snapshot taken in the session.

```bash
# Typical workflow: snapshot -> action -> diff
agent-browser snapshot -i          # Take baseline snapshot
agent-browser click @e2            # Perform action
agent-browser diff snapshot        # See what changed (auto-compares to last snapshot)
```

`diff snapshot` output uses `+` for additions and `-` for removals, similar to git diff. `diff screenshot` produces a diff image with changed pixels highlighted in red, plus a mismatch percentage.

### Wait

```bash
agent-browser wait @e1                     # Wait for element
agent-browser wait 2000                    # Wait milliseconds
agent-browser wait --text "Success"        # Wait for text (or -t)
agent-browser wait --url "**/dashboard"    # Wait for URL pattern (or -u)
agent-browser wait --load networkidle      # Wait for network idle (or -l)
agent-browser wait --fn "window.ready"     # Wait for JS condition (or -f)
```

### Mouse control

```bash
agent-browser mouse move 100 200      # Move mouse
agent-browser mouse down left         # Press button
agent-browser mouse up left           # Release button
agent-browser mouse wheel 100         # Scroll wheel
```

### Semantic locators (alternative to refs)

When refs are unavailable or unreliable, use semantic locators:

```bash
agent-browser find role button click --name "Submit"
agent-browser find text "Sign In" click
agent-browser find text "Sign In" click --exact      # Exact match only
agent-browser find label "Email" fill "user@test.com"
agent-browser find placeholder "Search" type "query"
agent-browser find alt "Logo" click
agent-browser find title "Close" click
agent-browser find testid "submit-btn" click
agent-browser find first ".item" click
agent-browser find last ".item" click
agent-browser find nth 2 "a" hover
```

### Browser settings

```bash
agent-browser set viewport 1920 1080          # Set viewport size
agent-browser set device "iPhone 14"          # Emulate device
agent-browser set geo 37.7749 -122.4194       # Set geolocation (alias: geolocation)
agent-browser set offline on                  # Toggle offline mode
agent-browser set headers '{"X-Key":"v"}'     # Extra HTTP headers
agent-browser set credentials user pass       # HTTP basic auth (alias: auth)
agent-browser set media dark                  # Emulate color scheme
agent-browser set media light reduced-motion  # Light mode + reduced motion
```

### Cookies & Storage

```bash
agent-browser cookies                     # Get all cookies
agent-browser cookies set name value      # Set cookie
agent-browser cookies clear               # Clear cookies
agent-browser storage local               # Get all localStorage
agent-browser storage local key           # Get specific key
agent-browser storage local set k v       # Set value
agent-browser storage local clear         # Clear all
```

### Network

```bash
agent-browser network route <url>              # Intercept requests
agent-browser network route <url> --abort      # Block requests
agent-browser network route <url> --body '{}'  # Mock response
agent-browser network unroute [url]            # Remove routes
agent-browser network requests                 # View tracked requests
agent-browser network requests --filter api    # Filter requests
```

### Tabs & Windows

```bash
agent-browser tab                 # List tabs
agent-browser tab new [url]       # New tab
agent-browser tab 2               # Switch to tab by index
agent-browser tab close           # Close current tab
agent-browser tab close 2         # Close tab by index
agent-browser window new          # New window
```

### Frames

```bash
agent-browser frame "#iframe"     # Switch to iframe
agent-browser frame main          # Back to main frame
```

### Dialogs

```bash
agent-browser dialog accept [text]  # Accept dialog
agent-browser dialog dismiss        # Dismiss dialog
```

### JavaScript (eval)

Use `eval` to run JavaScript in the browser context. **Shell quoting can corrupt complex expressions** -- use `--stdin` or `-b` to avoid issues.

```bash
# Simple expressions work with regular quoting
agent-browser eval 'document.title'
agent-browser eval 'document.querySelectorAll("img").length'

# Complex JS: use --stdin with heredoc (RECOMMENDED)
agent-browser eval --stdin <<'EVALEOF'
JSON.stringify(
  Array.from(document.querySelectorAll("img"))
    .filter(i => !i.alt)
    .map(i => ({ src: i.src.split("/").pop(), width: i.width }))
)
EVALEOF

# Alternative: base64 encoding (avoids all shell escaping issues)
agent-browser eval -b "$(echo -n 'Array.from(document.querySelectorAll("a")).map(a => a.href)' | base64)"
```

**Rules of thumb:**
- Single-line, no nested quotes -> regular `eval 'expression'` with single quotes is fine
- Nested quotes, arrow functions, template literals, or multiline -> use `eval --stdin <<'EVALEOF'`
- Programmatic/generated scripts -> use `eval -b` with base64

### Profiling

```bash
agent-browser profiler start         # Start Chrome DevTools profiling
agent-browser profiler stop trace.json # Stop and save profile (path optional)
```

## Global options

```bash
agent-browser --session <name> ...    # Isolated browser session
agent-browser --session-name <name> ...  # Named session with auto-save/restore
agent-browser --json ...              # JSON output for parsing
agent-browser --headed ...            # Show browser window (not headless)
agent-browser --full ...              # Full page screenshot (-f)
agent-browser --cdp <port> ...        # Connect via Chrome DevTools Protocol
agent-browser --auto-connect ...      # Auto-discover running Chrome with remote debugging
agent-browser -p <provider> ...       # Cloud browser provider (--provider)
agent-browser --proxy <url> ...       # Use proxy server
agent-browser --headers <json> ...    # HTTP headers scoped to URL's origin
agent-browser --executable-path <p>   # Custom browser executable
agent-browser --extension <path> ...  # Load browser extension (repeatable)
agent-browser --allow-file-access ... # Allow file:// URL access for local files
agent-browser --ignore-https-errors ...  # Ignore HTTPS certificate errors
agent-browser --config <path> ...     # Custom config file path
agent-browser --help                  # Show help (-h)
agent-browser --version               # Show version (-V)
agent-browser <command> --help        # Show detailed help for a command
```

### Proxy support

```bash
agent-browser --proxy http://proxy.com:8080 open example.com
agent-browser --proxy http://user:pass@proxy.com:8080 open example.com
agent-browser --proxy socks5://proxy.com:1080 open example.com
```

## Environment variables

```bash
AGENT_BROWSER_SESSION="mysession"            # Default session name
AGENT_BROWSER_EXECUTABLE_PATH="/path/chrome" # Custom browser path
AGENT_BROWSER_EXTENSIONS="/ext1,/ext2"       # Comma-separated extension paths
AGENT_BROWSER_PROVIDER="your-cloud-browser-provider"  # Cloud browser provider (select browseruse or browserbase)
AGENT_BROWSER_STREAM_PORT="9223"             # WebSocket streaming port
AGENT_BROWSER_HOME="/path/to/agent-browser"  # Custom install location (for daemon.js)
AGENT_BROWSER_ENCRYPTION_KEY="<hex>"         # Encrypt session state at rest
AGENT_BROWSER_CONFIG="/path/to/config.json"  # Custom config file path
```

## Configuration file

Create `agent-browser.json` in the project root for persistent settings:

```json
{
  "headed": true,
  "proxy": "http://localhost:8080",
  "profile": "./browser-data"
}
```

Priority (lowest to highest): `~/.agent-browser/config.json` < `./agent-browser.json` < env vars < CLI flags. Use `--config <path>` or `AGENT_BROWSER_CONFIG` env var for a custom config file. All CLI options map to camelCase keys (e.g., `--executable-path` -> `"executablePath"`). Boolean flags accept `true`/`false` values. Extensions from user and project configs are merged, not replaced.

## Ref lifecycle (important)

Refs (`@e1`, `@e2`, etc.) are invalidated when the page changes. Always re-snapshot after:

- Clicking links or buttons that navigate
- Form submissions
- Dynamic content loading (dropdowns, modals)

```bash
agent-browser click @e5              # Navigates to new page
agent-browser snapshot -i            # MUST re-snapshot
agent-browser click @e1              # Use new refs
```

## Annotated screenshots (vision mode)

Use `--annotate` to take a screenshot with numbered labels overlaid on interactive elements. Each label `[N]` maps to ref `@eN`. This also caches refs, so you can interact with elements immediately without a separate snapshot.

```bash
agent-browser screenshot --annotate
# Output includes the image path and a legend:
#   [1] @e1 button "Submit"
#   [2] @e2 link "Home"
#   [3] @e3 textbox "Email"
agent-browser click @e2              # Click using ref from annotated screenshot
```

Use annotated screenshots when:
- The page has unlabeled icon buttons or visual-only elements
- You need to verify visual layout or styling
- Canvas or chart elements are present (invisible to text snapshots)
- You need spatial reasoning about element positions

## Timeouts and slow pages

The default Playwright timeout is 60 seconds for local browsers. For slow websites or large pages, use explicit waits instead of relying on the default timeout:

```bash
agent-browser wait --load networkidle      # Wait for network activity to settle (best for slow pages)
agent-browser wait "#content"              # Wait for a specific element to appear
agent-browser wait @e1                     # Wait for element by ref
agent-browser wait --url "**/dashboard"    # Wait for URL pattern (useful after redirects)
agent-browser wait --fn "document.readyState === 'complete'"  # Wait for JS condition
agent-browser wait 5000                    # Wait fixed duration (milliseconds) as last resort
```

When dealing with consistently slow websites, use `wait --load networkidle` after `open` to ensure the page is fully loaded before taking a snapshot.

## Example: Form submission

```bash
agent-browser open https://example.com/form
agent-browser snapshot -i
# Output shows: textbox "Email" [ref=e1], textbox "Password" [ref=e2], button "Submit" [ref=e3]

agent-browser fill @e1 "user@example.com"
agent-browser fill @e2 "password123"
agent-browser click @e3
agent-browser wait --load networkidle
agent-browser snapshot -i  # Check result
```

## Example: Authentication with saved state

```bash
# Login once
agent-browser open https://app.example.com/login
agent-browser snapshot -i
agent-browser fill @e1 "username"
agent-browser fill @e2 "password"
agent-browser click @e3
agent-browser wait --url "**/dashboard"
agent-browser state save auth.json

# Later sessions: load saved state
agent-browser state load auth.json
agent-browser open https://app.example.com/dashboard
```

## Session persistence

```bash
# Auto-save/restore cookies and localStorage across browser restarts
agent-browser --session-name myapp open https://app.example.com/login
# ... login flow ...
agent-browser close  # State auto-saved to ~/.agent-browser/sessions/

# Next time, state is auto-loaded
agent-browser --session-name myapp open https://app.example.com/dashboard

# Encrypt state at rest
export AGENT_BROWSER_ENCRYPTION_KEY=$(openssl rand -hex 32)
agent-browser --session-name secure open https://app.example.com

# Manage saved states
agent-browser state list
agent-browser state show myapp-default.json
agent-browser state clear myapp
agent-browser state clean --older-than 7
```

## Sessions (parallel browsers)

```bash
agent-browser --session test1 open site-a.com
agent-browser --session test2 open site-b.com
agent-browser session list
```

Always close your browser session when done to avoid leaked processes:

```bash
agent-browser close                    # Close default session
agent-browser --session test1 close    # Close specific session
```

If a previous session was not closed properly, the daemon may still be running. Use `agent-browser close` to clean it up before starting new work.

## Data extraction

```bash
agent-browser open https://example.com/products
agent-browser snapshot -i
agent-browser get text @e5           # Get specific element text
agent-browser get text body > page.txt  # Get all page text

# JSON output for parsing
agent-browser snapshot -i --json
agent-browser get text @e1 --json
```

## Connect to existing Chrome

```bash
# Auto-discover running Chrome with remote debugging enabled
agent-browser --auto-connect open https://example.com
agent-browser --auto-connect snapshot

# Or with explicit CDP port
agent-browser --cdp 9222 snapshot
```

## Local files (PDFs, HTML)

```bash
# Open local files with file:// URLs
agent-browser --allow-file-access open file:///path/to/document.pdf
agent-browser --allow-file-access open file:///path/to/page.html
agent-browser screenshot output.png
```

## iOS Simulator (Mobile Safari)

```bash
# List available iOS simulators
agent-browser device list

# Launch Safari on a specific device
agent-browser -p ios --device "iPhone 16 Pro" open https://example.com

# Same workflow as desktop - snapshot, interact, re-snapshot
agent-browser -p ios snapshot -i
agent-browser -p ios tap @e1          # Tap (alias for click)
agent-browser -p ios fill @e2 "text"
agent-browser -p ios swipe up         # Mobile-specific gesture

# Take screenshot
agent-browser -p ios screenshot mobile.png

# Close session (shuts down simulator)
agent-browser -p ios close
```

**Requirements:** macOS with Xcode, Appium (`npm install -g appium && appium driver install xcuitest`)

**Real devices:** Works with physical iOS devices if pre-configured. Use `--device "<UDID>"` where UDID is from `xcrun xctrace list devices`.

## Debugging

```bash
agent-browser --headed open example.com   # Show browser window
agent-browser --cdp 9222 snapshot         # Connect via CDP port
agent-browser connect 9222                # Alternative: connect command
agent-browser console                     # View console messages
agent-browser console --clear             # Clear console
agent-browser errors                      # View page errors
agent-browser errors --clear              # Clear errors
agent-browser highlight @e1               # Highlight element
agent-browser trace start                 # Start recording trace
agent-browser trace stop trace.zip        # Stop and save trace
agent-browser record start ./debug.webm   # Record video from current page
agent-browser record stop                 # Save recording
agent-browser profiler start              # Start Chrome DevTools profiling
agent-browser profiler stop trace.json    # Stop and save profile
```

## HTTPS Certificate Errors

For sites with self-signed or invalid certificates:
```bash
agent-browser open https://localhost:8443 --ignore-https-errors
```

## Electron App Automation

Automate any Electron desktop app using agent-browser. Electron apps are built on Chromium and expose a Chrome DevTools Protocol (CDP) port that agent-browser can connect to, enabling the same snapshot-interact workflow used for web pages.

### Core Workflow

1. **Launch** the Electron app with remote debugging enabled
2. **Connect** agent-browser to the CDP port
3. **Snapshot** to discover interactive elements
4. **Interact** using element refs
5. **Re-snapshot** after navigation or state changes

```bash
# Launch an Electron app with remote debugging
open -a "Slack" --args --remote-debugging-port=9222

# Connect agent-browser to the app
agent-browser connect 9222

# Standard workflow from here
agent-browser snapshot -i
agent-browser click @e5
agent-browser screenshot slack-desktop.png
```

### Launching Electron Apps with CDP

Every Electron app supports the `--remote-debugging-port` flag since it's built into Chromium.

#### macOS

```bash
# Slack
open -a "Slack" --args --remote-debugging-port=9222

# VS Code
open -a "Visual Studio Code" --args --remote-debugging-port=9223

# Discord
open -a "Discord" --args --remote-debugging-port=9224

# Figma
open -a "Figma" --args --remote-debugging-port=9225

# Notion
open -a "Notion" --args --remote-debugging-port=9226

# Spotify
open -a "Spotify" --args --remote-debugging-port=9227
```

#### Linux

```bash
slack --remote-debugging-port=9222
code --remote-debugging-port=9223
discord --remote-debugging-port=9224
```

#### Windows

```bash
"C:\Users\%USERNAME%\AppData\Local\slack\slack.exe" --remote-debugging-port=9222
"C:\Users\%USERNAME%\AppData\Local\Programs\Microsoft VS Code\Code.exe" --remote-debugging-port=9223
```

**Important:** If the app is already running, quit it first, then relaunch with the flag. The `--remote-debugging-port` flag must be present at launch time.

### Connecting to Electron Apps

```bash
# Connect to a specific port
agent-browser connect 9222

# Or use --cdp on each command
agent-browser --cdp 9222 snapshot -i

# Auto-discover a running Chromium-based app
agent-browser --auto-connect snapshot -i
```

After `connect`, all subsequent commands target the connected app without needing `--cdp`.

### Tab Management

Electron apps often have multiple windows or webviews. Use tab commands to list and switch between them:

```bash
# List all available targets (windows, webviews, etc.)
agent-browser tab

# Switch to a specific tab by index
agent-browser tab 2

# Switch by URL pattern
agent-browser tab --url "*settings*"
```

### Common Electron Patterns

#### Inspect and Navigate an App

```bash
open -a "Slack" --args --remote-debugging-port=9222
sleep 3  # Wait for app to start
agent-browser connect 9222
agent-browser snapshot -i
# Read the snapshot output to identify UI elements
agent-browser click @e10  # Navigate to a section
agent-browser snapshot -i  # Re-snapshot after navigation
```

#### Take Screenshots of Desktop Apps

```bash
agent-browser connect 9222
agent-browser screenshot app-state.png
agent-browser screenshot --full full-app.png
agent-browser screenshot --annotate annotated-app.png
```

#### Extract Data from a Desktop App

```bash
agent-browser connect 9222
agent-browser snapshot -i
agent-browser get text @e5
agent-browser snapshot --json > app-state.json
```

#### Fill Forms in Desktop Apps

```bash
agent-browser connect 9222
agent-browser snapshot -i
agent-browser fill @e3 "search query"
agent-browser press Enter
agent-browser wait 1000
agent-browser snapshot -i
```

#### Run Multiple Apps Simultaneously

Use named sessions **only** when you need to control multiple Electron apps at the same time. Each session spawns a separate Chromium process (~300MB RAM), so only create multiple sessions when explicitly required and close each one when done.

```bash
# Connect to Slack
agent-browser --session slack connect 9222

# Connect to VS Code
agent-browser --session vscode connect 9223

# Interact with each independently
agent-browser --session slack snapshot -i
agent-browser --session vscode snapshot -i

# Close sessions when done
agent-browser --session slack close
agent-browser --session vscode close
```

### Color Scheme

Playwright overrides the color scheme to `light` by default when connecting via CDP. To preserve dark mode:

```bash
agent-browser connect 9222
agent-browser --color-scheme dark snapshot -i
```

Or set it globally:

```bash
AGENT_BROWSER_COLOR_SCHEME=dark agent-browser connect 9222
```

### Electron Troubleshooting

#### "Connection refused" or "Cannot connect"

- Make sure the app was launched with `--remote-debugging-port=NNNN`
- If the app was already running, quit and relaunch with the flag
- Check that the port isn't in use by another process: `lsof -i :9222`

#### App launches but connect fails

- Wait a few seconds after launch before connecting (`sleep 3`)
- Some apps take time to initialize their webview

#### Elements not appearing in snapshot

- The app may use multiple webviews. Use `agent-browser tab` to list targets and switch to the right one
- Use `agent-browser snapshot -i -C` to include cursor-interactive elements (divs with onclick handlers)

#### Cannot type in input fields

- Try `agent-browser keyboard type "text"` to type at the current focus without a selector
- Some Electron apps use custom input components; use `agent-browser keyboard inserttext "text"` to bypass key events

## CRITICAL:
1. Screenshots are required for UI testing. Text snapshots do not catch layout issues, styling problems, alignment, z-index issues, etc. Always use `agent-browser screenshot --annotate` to get numbered element labels overlaid on the screenshot, which enables both visual verification and immediate interaction via refs.
2. **Use a single browser session.** Do not create multiple `--session` names — each spawns a separate Chromium process (~300MB RAM). Use one session and call `agent-browser open <new-url>` to navigate between pages within it. If you must create a new session, close the previous one first with `agent-browser --session <name> close`. **Exception:** When controlling multiple Electron apps simultaneously on different CDP ports, multiple named sessions are acceptable — but only when the user explicitly needs it, and each session must be closed when no longer needed.
3. When done, close your browser with `agent-browser close` (or `agent-browser --session <name> close`) to free resources.
4. **Electron apps: quit first.** If the Electron app is already running, you must quit it completely before relaunching with `--remote-debugging-port`. The flag only takes effect at launch time.