Firefox Browser Agent Bridge

Control the user's actual Firefox browser session via WebSocket. This uses their real browser with existing logins and cookies - not a headless browser.

Quick Start

# 0. If Firefox isn't running, start it first
nohup firefox &>/dev/null &

# 1. Check connection
browser ping

# 2. See what tabs are open
browser listTabs '{}'

# 3. Start a new session (recommended)
browser newSession '{"url": "https://example.com"}'

# 4. Read the page with interactable elements marked
browser getContent '{"format": "annotated"}'

Client Usage

browser <action> '<json_params>'

Actions Reference

Session & Tab Management

Action	Description	Key Params
listTabs	List all open tabs across windows	-
newSession	Create new tab to work in	url (optional)
newWindow	Create a new normal window to work in	url (optional), focus (defaults true), sandbox (private window)
setActiveTab	Switch which tab agent works on	tabId, focus
getActiveTab	Get current tab info	-

Navigation & Page Info

Action	Description	Key Params
navigate	Go to URL in current tab	url, wait, newTab
getContent	Get page content	format: annotated, text, html
getInteractables	List clickable elements and inputs	selector (optional scope)
screenshot	Capture visible area as PNG	filename (optional)

Interaction

Action	Description	Key Params
click	Click element	selector, text, or x/y coords
type	Type into input	selector, text, submit, clear
fillForm	Fill multiple fields	fields[] with selector/value pairs
waitFor	Wait for element/text	selector, text, timeout
scroll	Scroll the page	y/x, selector, position
evaluate	Execute JavaScript and return result	script

Control Flow

Action	Description	Key Params
fork	Duplicate tab into multiple paths	paths[] with name + commands
killFork	Close a fork	fork (name)
listForks	List active forks	-
tryUntil	Try alternatives until one succeeds	alternatives[], timeout
parallel	Run commands on multiple URLs	branches[] with url + commands

Authentication & Vault

Action	Description	Key Params
autoLogin	Auto-fill credentials from Bitwarden vault and optionally submit	domain, submit (default false)
vaultStatus	Check vault lock state and credential count	-
vaultSync	Re-sync vault from Bitwarden server via API key	-
getAuthContext	Detect login pages, available accounts	-
requestAuth	Request user approval for auth	reason

---

Rich Text Editors (ProseMirror, Lexical, Slate, etc.)

The type and fillForm actions automatically handle rich text editors (ProseMirror, Lexical/Reddit, Draft.js, Tiptap, Slate, CKEditor, Quill). They use document.execCommand("insertText") in the page world, which works with any contenteditable-based editor.

# Works on any rich text editor — ProseMirror, Lexical, etc.
browser type '{"selector": "div[contenteditable=true]", "text": "Hello world!"}'
# Response includes richEditor: true when execCommand path was used

# Clear existing content and replace
browser type '{"selector": ".ProseMirror", "text": "New content", "clear": true}'

# Fill multiple rich text fields in a form
browser fillForm '{"fields": [
  {"selector": "#title", "value": "My Title"},
  {"selector": "#body .ProseMirror", "value": "Article body text"}
]}'

No special handling needed — just use type or fillForm as normal. Falls back to textContent assignment if execCommand isn't available.

---

1. Start by Inspecting Available Tabs

browser listTabs '{}'

Returns:

{
  "activeTabId": 123,
  "windows": [
    {
      "windowId": 1,
      "focused": true,
      "tabs": [
        {"tabId": 123, "url": "https://...", "title": "...", "active": true}
      ]
    }
  ],
  "totalTabs": 5
}

2. Start Fresh or Pick Existing Tab

# Start fresh in a tab
browser newSession '{"url": "https://amazon.com"}'

# Start fresh in a new normal window
browser newWindow '{"url": "https://example.com"}'

# Or switch to existing tab
browser setActiveTab '{"tabId": 456}'

3. Read Page with Annotated Format (Recommended)

browser getContent '{"format": "annotated"}'

Returns content with interactive elements marked inline:

Product Name Here
$4.99
[button: "Add to cart" | selector: #add-btn]
[input:text: "search" | value: "" | selector: #search-box]
[link: "View details" | href: /product/123 | selector: a.details-link]

This shows what's clickable and where it is in context.

4. Interact Using Selectors

# Click using selector from annotated output
browser click '{"selector": "#add-btn"}'

# Or by text (prefers visible elements)
browser click '{"text": "Add to cart"}'

# Type into input
browser type '{"selector": "#search-box", "text": "query", "submit": true}'

---

Fork: Speculative Parallel Execution

When you're not sure which path is right, fork the tab and try both:

# Create forks
browser fork '{
  "paths": [
    {
      "name": "google-auth",
      "commands": [{"action": "click", "params": {"text": "Sign in with Google"}}]
    },
    {
      "name": "email-auth",
      "commands": [{"action": "click", "params": {"text": "Sign in with Email"}}]
    }
  ]
}'

Returns:

{
  "forked": true,
  "sourceTabId": 123,
  "forks": [
    {"name": "google-auth", "tabId": 456, "url": "...", "commandResults": [...]},
    {"name": "email-auth", "tabId": 789, "url": "...", "commandResults": [...]}
  ]
}

Work on specific fork:

browser getContent '{"format": "annotated", "fork": "google-auth"}'
browser click '{"text": "Continue", "fork": "google-auth"}'

Kill the wrong path:

browser killFork '{"fork": "email-auth"}'

---

TryUntil: Handle Uncertain UI

When the exact button varies (cookie banners, A/B tests):

browser tryUntil '{
  "alternatives": [
    {"action": "click", "params": {"selector": "#accept-cookies"}},
    {"action": "click", "params": {"text": "Accept All"}},
    {"action": "click", "params": {"selector": ".cookie-dismiss"}}
  ],
  "timeout": 3000
}'

Tries each until one succeeds.

---

Parallel: Multiple URLs at Once

Compare prices across sites:

browser parallel '{
  "branches": [
    {"url": "https://amazon.com/product", "commands": [{"action": "getContent", "params": {"format": "text"}}]},
    {"url": "https://walmart.com/product", "commands": [{"action": "getContent", "params": {"format": "text"}}]}
  ]
}'

---

Authentication (Autonomous Login)

The bridge integrates with a Bitwarden vault (via bronzewarden) for fully autonomous credential fill. No human interaction needed.

Auto-Login Flow

# 1. Navigate to the site
browser navigate '{"url": "https://github.com"}'

# 2. Auto-fill credentials (looks up domain in vault, fills form)
browser autoLogin '{"domain": "github.com", "submit": false}'
# Returns: {"filled": true, "maskedUsername": "j***1", "matchedUri": "https://github.com/"}

# 3. Or auto-fill AND submit in one step
browser autoLogin '{"domain": "github.com", "submit": true}'

Vault Management

# Check vault status
browser vaultStatus '{}'
# Returns: {"locked": false, "entries": 322}

# Re-sync vault from server (if credentials were updated)
browser vaultSync '{}'
# Returns: {"synced": true, "entries": 322}

How It Works

• Credentials are stored in Bitwarden and decrypted locally by the native host
• The autoLogin action sends credentials directly to the extension via the native messaging channel (never over WebSocket)
• Vault is auto-unlocked at host startup using a master password from the system keyring

Legacy Auth Detection

# Detect login pages and available accounts
browser getAuthContext '{}'

---

Evaluate: Run JavaScript and Get Results

Execute arbitrary JavaScript in the page context and get the result back:

# Get page title
browser evaluate '{"script": "return document.title"}'
# Returns: {"result": "My Page Title", "type": "string"}

# Count elements
browser evaluate '{"script": "return document.querySelectorAll(\"input\").length"}'
# Returns: {"result": 5, "type": "number"}

# Get form values
browser evaluate '{"script": "return document.querySelector(\"#email\").value"}'
# Returns: {"result": "user@example.com", "type": "string"}

# Complex queries
browser evaluate '{"script": "return Array.from(document.querySelectorAll(\"input:checked\")).map(el => el.value)"}'
# Returns: {"result": ["option1", "option3"], "type": "object"}

Page World Evaluation

By default, evaluate runs in the content script's isolated world. To access page-level JavaScript variables (e.g., framework state, global objects set by the page), use pageWorld: true:

# Access page-level globals (React state, editor instances, app data)
browser evaluate '{"script": "return window.__NEXT_DATA__", "pageWorld": true}'

# Interact with ProseMirror/Lexical internals
browser evaluate '{"script": "return Object.keys(window.__prosemirrorViews || {})", "pageWorld": true}'

# Call page-level functions
browser evaluate '{"script": "return window.myApp.getState()", "pageWorld": true}'

Note: Use return to get a value back. The script runs with full DOM access. Use pageWorld: true when you need to access variables set by the page's own JavaScript.

---

Scroll: Navigate Long Pages

Scroll the page by pixels, to elements, or to positions:

# Scroll down 500 pixels
browser scroll '{"y": 500}'

# Scroll up 300 pixels
browser scroll '{"y": -300}'

# Scroll element into view
browser scroll '{"selector": "#section-5"}'

# Scroll to top/bottom
browser scroll '{"position": "top"}'
browser scroll '{"position": "bottom"}'

# Smooth scrolling
browser scroll '{"y": 500, "behavior": "smooth"}'

# Scroll to absolute position
browser scroll '{"scrollTo": {"x": 0, "y": 1000}}'

---

Form State in Annotated Content

The getContent annotated format now shows form element states:

browser getContent '{"format": "annotated"}'

Output includes checked/selected states:

[input:radio: "Option A" | checked: true | selector: #opt-a]
[input:radio: "Option B" | checked: false | selector: #opt-b]
[input:checkbox: "Remember me" | checked: true | selector: #remember]
[select: "Country" | selected: "United States" | selector: #country]
[input:text: "Email" | value: "user@example.com" | selector: #email]

This is useful for verifying form state without screenshots.

---

Isolated Sessions (for Parallel Execution)

When running multiple tasks in parallel, use tabId to avoid conflicts:

# 1. Create isolated session - get a unique tabId
browser newSession '{"url": "https://example.com"}'
# Returns: {"tabId": 15, "url": "...", "windowId": 1}

# 2. Use that tabId in ALL subsequent commands
browser navigate '{"url": "https://example.com/page", "tabId": 15}'
browser getContent '{"format": "annotated", "tabId": 15}'
browser click '{"selector": "#btn", "tabId": 15}'
browser type '{"selector": "#input", "text": "hello", "tabId": 15}'

This lets multiple agents work in parallel without stepping on each other.

Tips

1. Start with listTabs to see what's open
2. Use newSession for a clean new tab or newWindow for a separate window
3. Use tabId for parallel/isolated execution
4. Use annotated format - shows content + clickable elements together
5. Use selectors from annotated output - more reliable than text matching
6. Fork when uncertain - try multiple paths, kill the wrong ones

Troubleshooting

1. Firefox not running? Start it: nohup firefox &>/dev/null &
2. Check connection: browser ping
3. Connection refused? The extension may need to be reloaded in about:debugging
4. Element not found? Use browser getContent '{"format": "annotated"}' to see what's on the page