MCP server for loading authenticated web pages using Chrome DevTools Protocol
io.github.cherchyk/browser MCP Server
This MCP server, io.github.cherchyk/browser, enables loading authenticated web pages by using the Chrome DevTools Protocol. It is an MCP integration intended for browser automation scenarios where access to protected content is required. The project is distributed under the “MCPBrowser (MCP Browser)” name.
🛠️ Key Features
Loads authenticated web pages
Uses Chrome DevTools Protocol for browser control
🚀 Use Cases
Accessing and retrieving content from authenticated websites
Automating web page loading workflows via DevTools
⚡ Developer Benefits
Aligns browser automation with the Chrome DevTools Protocol
Provides an MCP server interface for authenticated page loading
⚠️ Limitations
Scope is limited to authenticated web page loading via Chrome DevTools Protocol
⚠️ Security Notice: MCPBrowser extracts webpage content and provides it to your AI agent (e.g., GitHub Copilot, Claude, Kiro, Antigravity), which then sends it to the LLM provider it uses (e.g., Anthropic, OpenAI, GitHub) for processing. Make sure you trust both your agent and the LLM provider — especially when accessing pages with sensitive or private data. MCPBrowser combines private data access, untrusted content exposure, and external communication (the MCP "lethal trifecta") — all tool annotations accurately declare these risks so MCP clients can enforce appropriate safety controls. See MCPBrowser/docs/MCP_COMPLIANCE.md for details.
💡 Why MCPBrowser over Puppeteer/Playwright MCP servers? Puppeteer and Playwright are browser automation libraries — their MCP servers give agents raw, low-level browser commands. MCPBrowser uses Puppeteer under the hood and was built specifically for AI agents, adding an intelligence layer that handles the hard parts automatically.
The agent gets clean HTML (90% smaller), automatic SPA detection (React, Vue, Angular), authentication flow handling (SSO, redirects, multi-step login), form discovery with multi-field filling, structured responses with next-step guidance, domain-based tab reuse, and instant DOM re-extraction without page reloads. Each MCPBrowser tool call replaces 5-8 raw browser automation calls — a typical 4-step workflow in MCPBrowser would take 20+ calls with Puppeteer/Playwright MCP, saving tokens and making the agent significantly faster. See full comparison below.
MCPBrowser is an MCP browser server that gives AI assistants the ability to browse web pages using a real Chrome, Edge, or Brave browser. This browser-based MCP server lets AI assistants (Claude, Copilot, Kiro, Antigravity) access any website — especially those protected by authentication, CAPTCHAs, anti-bot restrictions, or requiring JavaScript rendering. Uses your real browser session for web automation, so you log in once, and your AI can navigate, click buttons, fill forms, and extract content from sites that block automated requests.
Built on the Model Context Protocol (MCP), this web browser MCP server works seamlessly with Claude Desktop, Claude Code (CLI), GitHub Copilot, Kiro, Antigravity, and any MCP-compatible AI assistant. It handles corporate SSO, CAPTCHAs, Cloudflare protection, SPAs, dashboards, and any site that blocks automated requests. Your AI gets the same browser access you have — no special APIs, no headless browser detection, just your authenticated browser session.
Example workflow for AI assistant to use MCPBrowser
code
1. browser_fetch_webpage → Load the login page
2. browser_type_text → Enter username & password (multiple fields at once)
3. browser_click_element → Click "Sign In"
4. browser_get_current_html → Extract the content after login
Note: Node.js must be installed on your system. The VS Code extension and npm package both require Node.js to run the MCP server. Download from nodejs.org if not already installed.
Why MCPBrowser over Puppeteer/Playwright MCP servers?
Puppeteer and Playwright are browser automation libraries — their MCP servers expose low-level browser commands and the agent has to handle SPAs, auth flows, messy HTML, and edge cases on its own. MCPBrowser was built specifically for AI agents. It uses Puppeteer under the hood and adds an intelligence layer so the agent can focus on the task instead of fighting the browser.
Go to Cursor Settings -> MCP -> Add new MCP Server. Name to your liking, use command type with the command npx -y mcpbrowser@latest. You can also verify config or add command like arguments via clicking Edit.
Factory
Use the Factory CLI to add the MCPBrowser MCP server:
Go to Advanced settings -> Extensions -> Add custom extension. Name to your liking, use type STDIO, and set the command to npx -y mcpbrowser@latest. Click "Add Extension".
Kiro
Follow the MCP Servers documentation. For example in .kiro/settings/mcp.json:
The extension automatically installs and configures everything for your AI agent (GitHub Copilot, Kiro Agent, Antigravity Agent). Also works with VSCodium and other Open VSX-compatible editors.
Warp
Go to Settings -> AI -> Manage MCP Servers -> + Add to add an MCP Server. Use the standard config above.
Alternatively, use the slash command /add-mcp in the Warp prompt and paste the standard config from above.
Windsurf
Follow Windsurf MCP documentation. Use the standard config above.
MCP Tools
browser_fetch_webpage
Fetches web pages using your Chrome/Edge/Brave browser. Handles authentication, CAPTCHA, SSO, anti-bot protection, and JavaScript-heavy sites. Opens the URL in a browser tab (reuses existing tab for same domain) and waits for the page to fully load before returning content. Automatically detects SPAs (React, Vue, Angular) and waits for JavaScript to render content.
Parameters:
url (string, required) - The URL to fetch
removeUnnecessaryHTML (boolean, optional, default: true) - Remove unnecessary HTML for size reduction by ~90%
postLoadWait (number, optional, default: 0) - Additional milliseconds to wait after page load before extracting HTML. Use for pages that need extra time to render.
Examples:
javascript
// Basic fetch
{ url: "https://example.com" }
// Fetch with extra wait time for slow-rendering pages
{ url: "https://dashboard.example.com", postLoadWait: 2000 }
// Keep full HTML without cleanup
{ url: "https://example.com", removeUnnecessaryHTML: false }
browser_execute_javascript
Executes a JavaScript snippet in the active page context and returns the result with metadata (execution time, truncation flag, URL-change detection). Use for structured data extraction (e.g., inbox rows) or JS-driven UI actions that are unreliable via protocol clicks.
⚠️ Note: Page must be already loaded via browser_fetch_webpage first.
Parameters:
url (string, required) - The URL of the page (must match a previously fetched page)
script (string, required) - JavaScript source to execute in page context
Returns: Serialized result (outerHTML for DOM nodes), type, executionTimeMs, truncated, urlChanged, currentUrl, and structured error on failure.
Examples:
javascript
// Extract structured data from a page
{
url: "https://mail.google.com/",
script: "[...document.querySelectorAll('tr.zA')].slice(0,5).map(r => ({sender: r.querySelector('.zF')?.textContent, subject: r.querySelector('.bog')?.textContent}))"
}
// Click an element via JS when protocol clicks fail
{ url: "https://example.com", script: "document.querySelector('#tricky-button').click(); return 'clicked';" }
// Return void (side-effect only)
{ url: "https://example.com", script: "localStorage.clear();", returnType: "void" }
browser_click_element
Clicks on any clickable element (buttons, links, divs with onclick handlers, etc.). Can target by CSS selector or visible text content. Automatically scrolls element into view and waits for page stability after clicking.
⚠️ Note: Page must be already loaded via browser_fetch_webpage first.
Parameters:
url (string, required) - The URL of the page (must match a previously fetched page)
selector (string, optional) - CSS selector for the element (e.g., #submit-btn, .login-button)
text (string, optional) - Text content to search for if selector not provided (e.g., "Sign In", "Submit")
returnHtml (boolean, optional, default: true) - Whether to wait for stability and return HTML after clicking. Set to false for fast form interactions (checkboxes, radio buttons)
removeUnnecessaryHTML (boolean, optional, default: true) - Remove unnecessary HTML for size reduction. Only used when returnHtml is true
postClickWait (number, optional, default: 1000) - Milliseconds to wait after click for SPAs to render dynamic content
waitForElementTimeout (number, optional, default: 1000) - Maximum time to wait for element in milliseconds
Examples:
javascript
// Click by text content
{ url: "https://example.com", text: "Sign In" }
// Click by CSS selector
{ url: "https://example.com", selector: "#login-button" }
// Click without waiting for HTML (fast checkbox toggle)
{ url: "https://example.com", selector: "#agree-checkbox", returnHtml: false }
// Click with custom wait time
{ url: "https://example.com", text: "Load More", postClickWait: 2000 }
Fallback behavior: If the native click times out after locating the element, MCPBrowser automatically retries with a JavaScript-based click. The response includes fallbackUsed, nativeAttempt, and fallbackAttempt metadata. If both attempts fail, the response lists both errors so you can choose another strategy.
browser_type_text
Types text into one or more input fields in a single call. Supports filling entire forms at once for efficient automation. Automatically clears existing text by default.
⚠️ Note: Page must be already loaded via browser_fetch_webpage first.
Parameters:
url (string, required) - The URL of the page (must match a previously fetched page)
fields (array, required) - Array of fields to fill. Each field object contains:
selector (string, required) - CSS selector for the input element (e.g., #username, input[name="email"])
text (string, required) - Text to type into the field
clear (boolean, optional, default: true) - Whether to clear existing text first
waitForElementTimeout (number, optional, default: 5000) - Maximum time to wait for element in milliseconds
returnHtml (boolean, optional, default: true) - Whether to wait for stability and return HTML after typing
removeUnnecessaryHTML (boolean, optional, default: true) - Remove unnecessary HTML for size reduction. Only used when returnHtml is true
postTypeWait (number, optional, default: 1000) - Milliseconds to wait after typing for SPAs to render dynamic content
Examples:
javascript
// Fill multiple fields at once (login form)
{
url: "https://example.com/login",
fields: [
{ selector: "#username", text: "john@example.com" },
{ selector: "#password", text: "secretpass123" }
]
}
// Single field input
{ url: "https://example.com", fields: [{ selector: "#search", text: "query" }] }
// Append text without clearing
{ url: "https://example.com", fields: [{ selector: "#notes", text: " additional text", clear: false }] }
// Fast form fill without HTML return
{
url: "https://example.com/signup",
fields: [
{ selector: "#firstName", text: "John" },
{ selector: "#lastName", text: "Doe" },
{ selector: "#email", text: "john@example.com" }
],
returnHtml: false
}
Error handling: If a field fails, the response indicates:
Which field number failed (e.g., "Failed on field 2 of 3")
Which fields were successfully filled
Clear guidance to NOT re-type already filled fields
browser_get_current_html
Gets the current HTML from an already-loaded page WITHOUT navigating or reloading. Much faster than browser_fetch_webpage since it only extracts the current DOM state. Use this after interactions (click, type) to get the updated page content efficiently.
⚠️ Note: Page must be already loaded via browser_fetch_webpage first.
Parameters:
url (string, required) - The URL of the page (must match a previously fetched page)
removeUnnecessaryHTML (boolean, optional, default: true) - Remove unnecessary HTML for size reduction by ~90%
Examples:
javascript
// Get current HTML after interactions
{ url: "https://example.com" }
// Get full HTML without cleanup
{ url: "https://example.com", removeUnnecessaryHTML: false }
Scrolls within an already-loaded page. Use before browser_take_screenshot to capture different parts of the page, or to bring elements into view before interaction. Supports multiple scroll modes:
By direction: Scroll up/down/left/right by pixel amount
To element: Scroll until a specific element is visible
To position: Scroll to absolute coordinates
⚠️ Note: Page must be already loaded via browser_fetch_webpage first.
Parameters:
url (string, required) - The URL of the page (must match a previously fetched page)
direction (string, optional) - Direction to scroll: up, down, left, right. Use with amount.
amount (number, optional, default: 500) - Pixels to scroll in the specified direction (~half a viewport)
selector (string, optional) - CSS selector of element to scroll into view. Ignores direction/amount.
x (number, optional) - Absolute horizontal scroll position. Use with y.
y (number, optional) - Absolute vertical scroll position. Use with x.
Examples:
javascript
// Scroll down by 500px (default)
{ url: "https://example.com", direction: "down" }
// Scroll down by 1000px
{ url: "https://example.com", direction: "down", amount: 1000 }
// Scroll an element into view
{ url: "https://example.com", selector: "#footer" }
// Scroll to specific position
{ url: "https://example.com", x: 0, y: 2000 }
// Scroll to top of page
{ url: "https://example.com", x: 0, y: 0 }
Returns: Current scroll position, page dimensions, and viewport size — useful for understanding where you are on the page.
browser_take_screenshot
Takes a screenshot of an already-loaded page for visual analysis. Useful when HTML parsing is insufficient — for example, pages with charts, images, complex layouts, popups, or visual content that's hard to understand from HTML alone. Returns a PNG image.
⚠️ Note: Page must be already loaded via browser_fetch_webpage first.
Parameters:
url (string, required) - The URL of the page (must match a previously fetched page)
fullPage (boolean, optional, default: false) - Capture the full scrollable page instead of just the viewport
Closes the browser tab for the given URL's hostname. Removes the page from the tab pool and forces a fresh session on the next visit to that hostname. Useful for clearing authentication state, managing memory, or starting fresh with a domain.
⚠️ Note: Uses exact hostname match (www.example.com and example.com are treated as different tabs).
Parameters:
url (string, required) - The URL whose hostname tab should be closed
Examples:
javascript
// Close tab for a domain
{ url: "https://example.com" }
// This will close the tab for portal.azure.com
{ url: "https://portal.azure.com/dashboard" }
Use cases:
Clear authentication/session state
Free up browser memory
Reset to fresh state before new login
CLI Mode
MCPBrowser can also be used as a standalone command-line tool, making it easy to use from shell scripts, CI/CD pipelines, or AI agents that work through shell commands (like GitHub Copilot CLI).
bash
# Show help
mcpbrowser --help# Fetch a page (handles auth, SSO, SPAs automatically)
mcpbrowser fetch https://eng.ms/docs/my-page
# Fetch with raw HTML output
mcpbrowser fetch https://github.com --browser chrome --raw
# Take a screenshot
mcpbrowser screenshot https://example.com --output page.png --full-page
# Click an element on a loaded page
mcpbrowser click https://example.com --selector "#login-btn"# Type into a form field
mcpbrowser type https://example.com --selector "input[name=q]" --text "search query"# Execute JavaScript
mcpbrowser exec https://example.com --script "document.title"# Get current HTML of a loaded page
mcpbrowser html https://example.com
CLI vs MCP mode: When run without arguments, MCPBrowser starts as an MCP server (stdin/stdout JSON-RPC). When run with a subcommand, it executes the command and exits — no MCP protocol needed.
Configuration (Optional)
Environment variables for advanced setup:
Variable
Description
Default
CHROME_PATH
Path to Chrome/Edge/Brave
Auto-detect
CHROME_USER_DATA_DIR
Browser profile directory
%LOCALAPPDATA%/ChromeAuthProfile
CHROME_REMOTE_DEBUG_PORT
DevTools port
9222
Troubleshooting
Browser doesn't open?
Make sure Chrome, Edge, or Brave is installed
Try setting CHROME_PATH explicitly
Can't connect to browser?
Close all Chrome instances and try again
Check if port 9222 is in use
Authentication not preserved?
Keep the browser tab open (default behavior)
Use the same domain for related requests
E401 error with npx / private npm registry?
If your project has a .npmrc that points to a private registry (e.g., Azure Artifacts, GitHub Packages, Artifactory), npx will try to fetch mcpbrowser from that registry instead of npmjs.org and fail with E401.
Fix: Add npm_config_registry to the env block in your MCP config:
