
SeleniumBase MCP
io.github.seleniumbasePublished by GitHub account seleniumbasev4.57.1Updated Nov 5, 2026
Stealthy browser automation, testing, and web-scraping via CDP Mode.
Overview
SeleniumBase MCP exposes the SeleniumBase Python framework so an assistant can drive a stealthy Chromium browser for automation, scraping and end-to-end…
- What you can do
- Navigate and interact with pages: open URLs, type, click, select, hover, drag and drop, switch frames and windows
- Read page state: get text, attributes, title, current URL and page source
- Verify results: assert elements, text, titles, downloads, 404s and JS errors, with automatic waits
- Capture output: save screenshots and export pages as PDF
- Run stealthy CDP Mode sessions that handle CAPTCHA and Cloudflare-style challenges
- Run pytest-style end-to-end test flows against web apps
- When to use it
- Useful when you want an assistant to exercise a real browser: smoke-testing a web app, filling and submitting forms, checking rendered content, or collecting page data from sites that block plain HTTP clients. It fits local, desktop-driven testing and scraping work rather than headless server deployments.
- Requirements
- Runs as a local process on the user's machine via uvx from the seleniumbase PyPI package, so Python and uv are needed. A desktop environment is required (desktop only, not web-executable). Chromium-based browsers are used; Chrome is the default and unbranded Chromium or Chrome-for-Testing are downloaded automatically if missing, and webdrivers are fetched as needed. No accounts, API keys or environment variables are declared.
Installation
In SourceWeft
- Open SeleniumBase MCP in the dashboard and add it to a workspace.
- Enable the server for the chats that should use its tools.
Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.
Other MCP clients
Follow the launch instructions in the repository.
README
[Image]
Browser Automation, Web Scraping, and End-to-End Testing.
[PyPI version] [SeleniumBase GitHub Actions] [SeleniumBase Docs] [Image] [Image] [SeleniumBase PyPI downloads]
[YouTube Channel] [SeleniumBase Facebook Followers] [SeleniumBase X Followers] [Image] [Image]
🚀 Start |
🏰 Features |
🎛️ Options |
📚 Examples |
💻 Scripts |
🗾 Locales
📗 API |
📘 Stealth API |
🔠 Syntax Formats |
🔴 Recorder |
📊 Dashboard
🎖️ GUI |
📰 Test Page |
👤 UC Mode |
🐙 CDP Mode |
📶 Charts |
🖥️ Farm
👁️ How |
🚝 Migration |
🎭 Stealthy Playwright |
🛂 MasterQA |
🚎 Tours
🤖 MCP |
🟨 JS Tools |
🌏 Translator |
🎞️ Presenter |
🖼️ Visual |
🗂️ CPlans
🧪 End-to-End Testing examples are located in ./examples/.
🐙 Stealthy CDP Mode examples are located in ./examples/cdp_mode/.
🎭 Stealthy Playwright examples are located in ./examples/cdp_mode/playwright/.
[!NOTE] Examples that start with
testrun withpytest.
Other examples run directly with rawpython.
📝 This example uses seleniumbase sb_cdp (Pure CDP Mode):
(It shows some basic methods and bypasses a Cloudflare Turnstile)
[Cloudflare Turnstile bypassed successfully]
(Note that the click action only unchecked the "Stay signed in" checkbox.)
✅ sb.solve_captcha() handles CAPTCHAs that aren't bypassed automatically.
(If called when there's no CAPTCHA on the page, then nothing happens / no-op.)
ℹ️ sb.assert_* methods wait up to 7 seconds for the expected condition.
(Raises an exception if the condition isn't met in time.)
📝 This script searches Hacker News via Algolia. Then prints items and saves to PDF:
📝 This script bypasses Cloudflare's challenge page with UC + CDP Mode:
🌐 CLI Options for Supported Chromium Browsers
💡 You can set which Chromium browser to use via command-line parameters:
Google Chrome is the default browser. Only unbranded Chromium and Chrome-for-Testing get downloaded automatically if not already present on the system.
The Chromium browser can also be set via method args, eg: cft=True, use_chromium=True, browser="edge", browser="brave", etc. Eg:
⚙️ Stealthy architecture flowchart:
[Stealthy architecture flowchart]🧪 Comprehensive E2E Testing with pytest:
📝 This script tests an e-commerce site: (Runs with pytest):
🥷 For stealth with pytest, add --uc as a command-line option.
📝 This script tests a different e-commerce site with pytest:
[SeleniumBase Coffee Cart Test]
(
--demomode slows down tests and highlights actions)
📝 This script covers multiple actions with pytest:
Easy to type, click, select, toggle, drag & drop, and more.
📚 For more scripts, see the SeleniumBase/examples/ folder.
Explore the README:
▶️ How is SeleniumBase different from raw Selenium? (click to expand)
💡 SeleniumBase is a Python framework for browser automation and testing. SeleniumBase uses Selenium/WebDriver APIs and incorporates test-runners such as pytest, pynose, and behave to provide organized structure, test discovery, test execution, test state (eg. passed, failed, or skipped), and command-line options for changing default settings (eg. browser selection). With raw Selenium, you would need to set up your own options-parser for configuring tests from the command-line.
💡 SeleniumBase's driver manager gives you more control over automatic driver downloads. (Use --driver-version=VER with your pytest run command to specify the version.) By default, SeleniumBase will download a driver version that matches your major browser version if not set.
💡 SeleniumBase automatically detects between CSS Selectors and XPath, which means you don't need to specify the type of selector in your commands (but optionally you could).
💡 SeleniumBase methods often perform multiple actions in a single method call. For example, self.type(selector, text) does the following:
1. Waits for the element to be visible.
2. Waits for the element to be interactive.
3. Clears the text field.
4. Types in the new text.
5. Presses Enter/Submit if the text ends in "\n".
With raw Selenium, those actions require multiple method calls.
💡 SeleniumBase uses default timeout values when not set:
✅ self.click("button")
With raw Selenium, methods would fail instantly (by default) if an element needed more time to load:
❌ self.driver.find_element(by="css selector", value="button").click()
(Reliable code is better than unreliable code.)
💡 SeleniumBase lets you change the explicit timeout values of methods:
✅ self.click("button", timeout=10)
With raw Selenium, that requires more code:
❌ WebDriverWait(driver, 10).until(EC.element_to_be_clickable("css selector", "button")).click()
(Simple code is better than complex code.)
💡 SeleniumBase gives you clean error output when a test fails. With raw Selenium, error messages can get very messy.
💡 SeleniumBase gives you the option to generate a dashboard and reports for tests. It also saves screenshots from failing tests to the ./latest_logs/ folder. Raw Selenium does not have these options out-of-the-box.
💡 SeleniumBase includes desktop GUI apps for running tests, such as SeleniumBase Commander for pytest and SeleniumBase Behave GUI for behave.
💡 SeleniumBase has its own Recorder / Test Generator for creating tests from manual browser actions.
💡 SeleniumBase comes with test case management software, ("CasePlans"), for organizing tests and step descriptions.
💡 SeleniumBase includes tools for building data apps, ("ChartMaker"), which can generate JavaScript from Python.
📚 Learn about different ways of writing tests:
📗📝 Here's test_simple_login.py, which uses BaseCase class inheritance, and runs with pytest or pynose. (Use self.driver to access Selenium's raw driver.)
📘📝 Here's raw_login_sb.py, which uses the SB Context Manager. Runs with pure python. (Use sb.driver to access Selenium's raw driver.)
📙📝 Here's raw_login_driver.py, which uses the Driver Manager. Runs with pure python. (The driver is an improved version of Selenium's raw driver, with more methods.)
[Image] Set up Python & Git:
🔵 Add Python and Git to your System PATH.
🔵 Using a Python virtual env is recommended.
[Image] Install SeleniumBase:
🔵 How to install seleniumbase from PyPI using pip:
- (Add
--upgradeOR-Uto upgrade SeleniumBase.) - (Add
--force-reinstallto upgrade indirect packages.)
🔵 How to install seleniumbase from a GitHub clone:
🔵 How to upgrade an existing install from a GitHub clone:
🔵 Type seleniumbase or sbase to verify that SeleniumBase was installed successfully:
🔵 Downloading webdrivers:
✅ SeleniumBase automatically downloads webdrivers as needed, such as chromedriver.
▶️ Here's sample output from a chromedriver download. (click to expand)
[Image] Basic Example / Usage:
🔵 If you've cloned SeleniumBase, you can run tests from the examples/ folder.
Here's my_first_test.py:
Here's the full code for my_first_test.py:
- By default, CSS Selectors are used for finding page elements.
- If you're new to CSS Selectors, games like CSS Diner can help you learn.
- For more reading, here's an advanced guide on CSS attribute selectors.
[Image] Here are some common SeleniumBase methods:
🔵 For the complete list of SeleniumBase methods, see: Method Summary
[Image] Fun Facts / Learn More:
✅ SeleniumBase automatically handles common WebDriver actions such as launching web browsers before tests, saving screenshots during failures, and closing web browsers after tests.
✅ SeleniumBase lets you customize tests via command-line options.
✅ SeleniumBase uses simple syntax for commands. Example:
Most SeleniumBase scripts can be run with pytest, pynose, or pure python. Not all test runners can run all test formats. For example, tests that use the sb pytest fixture can only be run with pytest. (See Syntax Formats) There's also a Gherkin test format that runs with behave.
✅ pytest includes automatic test discovery. If you don't specify a specific file or folder to run, pytest will automatically search through all subdirectories for tests to run based on the following criteria:
- Python files that start with
test_or end with_test.py. - Python methods that start with
test_.
With a SeleniumBase pytest.ini file present, you can modify default discovery settings. The Python class name can be anything because seleniumbase.BaseCase inherits unittest.TestCase to trigger autodiscovery.
✅ You can do a pre-flight check to see which tests would get discovered by pytest before the actual run:
✅ You can be more specific when calling pytest or pynose on a file:
✅ No More Flaky Tests! SeleniumBase methods automatically wait for page elements to finish loading before interacting with them (up to a timeout limit).
[NO MORE FLAKY TESTS!]✅ SeleniumBase supports all major browsers and operating systems:
Browsers: Chrome, Edge, Firefox, and Safari.
Systems: Linux/Ubuntu, macOS, and Windows.
✅ SeleniumBase works on all popular CI/CD platforms:
[GitHub Actions integration] [Jenkins integration] [Azure integration] [Google Cloud integration] [AWS integration] [Your Computer]
✅ SeleniumBase includes an automated/manual hybrid solution called MasterQA to speed up manual testing with automation while manual testers handle validation.
✅ SeleniumBase supports running tests while offline (assuming webdrivers have previously been downloaded when online).
✅ For a full list of SeleniumBase features, Click Here.
[Image] Demo Mode / Debugging:
🔵 Demo Mode helps you see what a test is doing. If a test is moving too fast for your eyes, run it in Demo Mode to pause the browser briefly between actions, highlight page elements being acted on, and display assertions:
🔵 time.sleep(seconds) can be used to make a test wait at a specific spot:
🔵 Debug Mode with Python's built-in pdb library helps you debug tests:
(
pdbcommands:n,c,s,u,d=>next,continue,step,up,down)
🔵 To pause an active test that throws an exception or error, (and keep the browser window open while Debug Mode begins in the console), add --pdb as a pytest option:
🔵 To start tests in Debug Mode, add --trace as a pytest option:
[SeleniumBase test with the pdbp (Pdb+) debugger]
🔵 Command-line Options:
✅ Here are some useful command-line options that come with pytest:
✅ SeleniumBase provides additional pytest command-line options for tests:
(See the full list of command-line option definitions here. For detailed examples of command-line options, see customizing_test_runs.md)
🔵 During test failures, logs and screenshots from the most recent test run will get saved to the latest_logs/ folder. Those logs will get moved to archived_logs/ if you add --archive_logs to command-line options, or have ARCHIVE_EXISTING_LOGS set to True in settings.py, otherwise log files with be cleaned up at the start of the next test run. The test_suite.py collection contains tests that fail on purpose so that you can see how logging works.
An easy way to override seleniumbase/config/settings.py is by using a custom settings file.
Here's the command-line option to add to tests: (See examples/custom_settings.py)
--settings_file=custom_settings.py
(Settings include default timeout values, a two-factor auth key, DB credentials, S3 credentials, and other important settings used by tests.)
🔵 To pass additional data from the command-line to tests, add --data="ANY STRING".
Inside your tests, you can use self.data to access that.
[Image] Directory Configuration:
🔵 When running tests with pytest, you'll want a copy of pytest.ini in your root folders. When running tests with pynose, you'll want a copy of setup.cfg in your root folders. These files specify default configuration details for tests. Test folders should also include a blank init.py file to allow your test files to import other files from that folder.
🔵 sbase mkdir DIR creates a folder with config files and sample tests:
That new folder will have these files:
ProTip™: You can also create a boilerplate folder without any sample tests in it by adding -b or --basic to the sbase mkdir command:
That new folder will have these files:
Of those files, the pytest.ini config file is the most important, followed by a blank __init__.py file. There's also a setup.cfg file (for pynose). Finally, the requirements.txt file can be used to help you install seleniumbase into your environments (if it's not already installed).
ProTip™: Add --gha to include a GitHub Actions .yml file with default settings:
[Image] Log files from failed tests:
Let's try an example of a test that fails:
You can run it from the examples/ folder like this:
🔵 You'll notice that a logs folder, ./latest_logs/, was created to hold information (and screenshots) about the failing test. During test runs, past results get moved to the archived_logs folder if you have ARCHIVE_EXISTING_LOGS set to True in settings.py, or if your run tests with --archive-logs. If you choose not to archive existing logs, they will be deleted and replaced by the logs of the latest test run.
[Image] SeleniumBase Dashboard:
🔵 The --dashboard option for pytest generates a SeleniumBase Dashboard located at dashboard.html, which updates automatically as tests run and produce results. Example:
🔵 Additionally, you can host your own SeleniumBase Dashboard Server on a port of your choice. Here's an example of that using Python's http.server:
🔵 Now you can navigate to http://localhost:1948/dashboard.html in order to view the dashboard as a web app. This requires two different terminal windows: one for running the server, and another for running the tests, which should be run from the same directory. (Use Ctrl+C to stop the http server.)
🔵 Here's a full example of what the SeleniumBase Dashboard may look like:
[The SeleniumBase Dashboard]
[Image] Generating Test Reports:
🔵 pytest HTML Reports:
✅ Using --html=report.html gives you a fancy report of the name specified after your test suite completes.
✅ When combining pytest html reports with SeleniumBase Dashboard usage, the pie chart from the Dashboard will get added to the html report. Additionally, if you set the html report URL to be the same as the Dashboard URL when also using the dashboard, (example: --dashboard --html=dashboard.html), then the Dashboard will become an advanced html report when all the tests complete.
✅ Here's an example of an upgraded html report:
[Dashboard Pytest HTML Report]If viewing pytest html reports in Jenkins, you may need to configure Jenkins settings for the html to render correctly. This is due to Jenkins CSP changes.
You can also use --junit-xml=report.xml to get an xml report instead. Jenkins can use this file to display better reporting for your tests.
🔵 pynose Reports:
The --report option gives you a fancy report after your test suite completes.
(NOTE: You can add --show-report to immediately display pynose reports after the test suite completes. Only use --show-report when running tests locally because it pauses the test run.)
🔵 behave Dashboard & Reports:
(The behave_bdd/ folder can be found in the examples/ folder.)
[Image]You can also use --junit to get .xml reports for each behave feature. Jenkins can use these files to display better reporting for your tests.
🔵 Allure Reports:
See: https://allurereport.org/docs/pytest/
SeleniumBase no longer includes allure-pytest as part of installed dependencies. If you want to use it, install it first:
Now your tests can create Allure results files, which can be processed by Allure Reports.
[Image] Using a Proxy Server:
If you wish to use a proxy server for your browser tests (Chromium or Firefox), you can add --proxy=IP_ADDRESS:PORT as an argument on the command line.
If the proxy server that you wish to use requires authentication, you can do the following (Chromium only):
SeleniumBase also supports SOCKS4 and SOCKS5 proxies:
To make things easier, you can add your frequently-used proxies to PROXY_LIST in proxy_list.py, and then use --proxy=KEY_FROM_PROXY_LIST to use the IP_ADDRESS:PORT of that key.
[Image] Changing the User-Agent:
🔵 If you wish to change the User-Agent for your browser tests (Chromium and Firefox only), you can add --agent="USER AGENT STRING" as an argument on the command-line.
[Image] Handling Pop-Up Alerts:
🔵 self.accept_alert() automatically waits for and accepts alert pop-ups. self.dismiss_alert() automatically waits for and dismisses alert pop-ups. On occasion, some methods like self.click(SELECTOR) might dismiss a pop-up on its own because they call JavaScript to make sure that the readyState of the page is complete before advancing. If you're trying to accept a pop-up that got dismissed this way, use this workaround: Call self.find_element(SELECTOR).click() instead, (which will let the pop-up remain on the screen), and then use self.accept_alert() to accept the pop-up (more on that here). If pop-ups are intermittent, wrap code in a try/except block.
[Image] Building Guided Tours for Websites:
🔵 Learn about SeleniumBase Interactive Walkthroughs (in the examples/tour_examples/ folder). It's great for prototyping a website onboarding experience.
[Image] Production Environments & Integrations:
▶️ Here are some things you can do to set up a production environment for your testing. (click to expand)
- You can set up a Jenkins build server for running tests at regular intervals. For a real-world Jenkins example of headless browser automation in action, check out the SeleniumBase Jenkins example on Azure or the SeleniumBase Jenkins example on Google Cloud.
- You can use the Selenium Grid to scale your testing by distributing tests on several machines with parallel execution. To do this, check out the SeleniumBase selenium_grid folder, which should have everything you need, including the Selenium Grid ReadMe to help you get started.
- If you're using the SeleniumBase MySQL feature to save results from tests running on a server machine, you can install MySQL Workbench to help you read & write from your DB more easily.
- If you're using AWS, you can set up an Amazon S3 account for saving log files and screenshots from your tests. To activate this feature, modify settings.py with connection details in the S3 section, and add
--with-s3-loggingon the command-line when running your tests.
Here's an example of running tests with some additional features enabled:
[Image] Detailed Method Specifications and Examples:
🔵 Navigating to a web page: (and related commands)
ProTip™: You can use the self.get_page_source() method with Python's find() command to parse through HTML to find something specific. (For more advanced parsing, see the BeautifulSoup example.)
🔵 Clicking:
To click an element on the page:
ProTip™: In most web browsers, you can right-click on a page and select Inspect Element to see the CSS selector details that you'll need to create your own scripts.
🔵 Typing Text:
self.type(selector, text) # updates the text from the specified element with the specified value. An exception is raised if the element is missing or if the text field is not editable. Example:
You can also use self.add_text() or the WebDriver .send_keys() command, but those won't clear the text box first if there's already text inside.
🔵 Getting the text from an element on a page:
🔵 Getting the attribute value from an element on a page:
🔵 Asserting existence of an element on a page within some number of seconds:
(NOTE: You can also use: self.assert_element_present(ELEMENT))
🔵 Asserting visibility of an element on a page within some number of seconds:
(NOTE: The short versions of that are self.find_element(ELEMENT) and self.assert_element(ELEMENT). The find_element() version returns the element.)
Since the line above returns the element, you can combine that with .click() as shown below:
ProTip™: You can use dots to signify class names (Ex: div.class_name) as a simplified version of div[class="class_name"] within a CSS selector.
You can also use *= to search for any partial value in a CSS selector as shown below:
🔵 Asserting visibility of text inside an element on a page within some number of seconds:
(NOTE: self.find_text(TEXT, ELEMENT) and self.wait_for_text(TEXT, ELEMENT) also do this. For backwards compatibility, older method names were kept, but the default timeout may be different.)
🔵 Asserting Anything:
🔵 Useful Conditional Statements: (with creative examples)
❓ is_element_visible(selector): (visible on the page)
❓ is_element_present(selector): (present in the HTML)
❓ is_text_visible(text, selector): (text visible on element)
▶️ Click for a longer example of is_text_visible():
❓ is_link_text_visible(link_text):
🔵 Switching Tabs:
If your test opens up a new tab/window, you can switch to it. (SeleniumBase automatically switches to new tabs that don't open to about:blank URLs.)
🔵 How to handle iframes:
🔵 iframes follow the same principle as new windows: You must first switch to the iframe if you want to perform actions in there:
To exit from multiple iframes, use self.switch_to_default_content(). (If inside a single iframe, this has the same effect as self.switch_to_parent_frame().)
🔵 You can also use a context manager to act inside iframes:
This also works with nested iframes:
🔵 How to execute custom jQuery scripts:
jQuery is a powerful JavaScript library that allows you to perform advanced actions in a web browser. If the web page you're on already has jQuery loaded, you can start executing jQuery scripts immediately. You'd know this because the web page would contain something like the following in the HTML:
🔵 It's OK if you want to use jQuery on a page that doesn't have it loaded yet. To do so, run the following command first:
▶️ Here are some examples of using jQuery in your scripts. (click to expand)
(Most of the above commands can be done directly with built-in SeleniumBase methods.)
🔵 How to handle a restrictive CSP:
❗ Some websites have a restrictive Content Security Policy to prevent users from loading jQuery and other external libraries onto their websites. If you need to use jQuery or another JS library on those websites, add --disable-csp as a pytest command-line option to load a Chromium extension that bypasses the CSP.
🔵 More JavaScript fun:
▶️ In this example, JavaScript creates a referral button on a page, which is then clicked. (click to expand)
(Due to popular demand, this traffic generation example has been included in SeleniumBase with the self.generate_referral(start_page, end_page) and the self.generate_traffic(start_page, end_page, loops) methods.)
🔵 How to use deferred asserts:
Let's say you want to verify multiple different elements on a web page in a single test, but you don't want the test to fail until you verified several elements at once so that you don't have to rerun the test to find more missing elements on the same page. That's where deferred asserts come in. Here's an example:
deferred_assert_element() and deferred_assert_text() will save any exceptions that would be raised.
To flush out all the failed deferred asserts into a single exception, make sure to call self.process_deferred_asserts() at the end of your test method. If your test hits multiple pages, you can call self.process_deferred_asserts() before navigating to a new page so that the screenshot from your log files matches the URL where the deferred asserts were made.
🔵 How to access raw WebDriver:
If you need access to any commands that come with standard WebDriver, you can call them directly like this:
(In general, you'll want to use the SeleniumBase versions of methods when available.)
🔵 How to retry failing tests automatically:
You can use pytest --reruns=NUM to retry failing tests that many times. Add --reruns-delay=SECONDS to wait that many seconds between retries. Example:
You can use the @retry_on_exception() decorator to retry failing methods. (First import: from seleniumbase import decorators). To learn more about SeleniumBase decorators, click here.
"Catch bugs in QA before deploying code to Production!"
[Catch bugs in QA before deploying code to Production!]
[Image] Wrap-Up
Source: README.md at commit d98668b
Tools
0Version history
17- v4.57.1LatestNov 5, 2026
- v4.57.0Nov 3, 2026
- v4.56.5Oct 29, 2026
- v4.56.4Oct 26, 2026
- v4.56.3Oct 21, 2026
- v4.56.2Oct 17, 2026
- v4.56.1Oct 12, 2026
- v4.56.0Oct 11, 2026
- v4.55.2Oct 8, 2026
- v4.55.1Oct 6, 2026
- v4.55.0Oct 2, 2026
- v4.54.13Sep 30, 2026
- v4.54.12Sep 26, 2026
- v4.54.11Sep 22, 2026
- v4.54.10Sep 18, 2026
- v4.54.8Sep 17, 2026
- v4.54.7Sep 16, 2026
Score
50% of the applicable checks met
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- Reached in the last 30 days25 pts
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- Auth declared10 pts
Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.
- Tools listed15 pts
Answer tools/list without a credential, or ship a package that starts in a sandbox without one.
- DescriptionRequired15 pts
- Logo10 pts
- Documentation15 pts
- License10 pts