tool-reference.md

Chrome DevTools MCP Tool Reference

• Input automation (7 tools)
  • click
  • drag
  • fill
  • fill_form
  • handle_dialog
  • hover
  • upload_file
• Navigation automation (7 tools)
  • close_page
  • list_pages
  • navigate_page
  • navigate_page_history
  • new_page
  • select_page
  • wait_for
• Emulation (3 tools)
  • emulate_cpu
  • emulate_network
  • resize_page
• Performance (3 tools)
  • performance_analyze_insight
  • performance_start_trace
  • performance_stop_trace
• Network (2 tools)
  • get_network_request
  • list_network_requests
• Debugging (4 tools)
  • evaluate_script
  • list_console_messages
  • take_screenshot
  • take_snapshot

Input automation

click

Description: Clicks on the provided element

Parameters:

• dblClick (boolean) (optional): Set to true for double clicks. Default is false.
• uid (string) (required): The uid of an element on the page from the page content snapshot

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drag

Description: Drag an element onto another element

Parameters:

• from_uid (string) (required): The uid of the element to drag
• to_uid (string) (required): The uid of the element to drop into

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fill

Description: Type text into a input, text area or select an option from a <select> element.

Parameters:

• uid (string) (required): The uid of an element on the page from the page content snapshot
• value (string) (required): The value to fill in

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fill_form

Description: Fill out multiple form elements at once

Parameters:

• elements (array) (required): Elements from snapshot to fill out.

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handle_dialog

Description: If a browser dialog was opened, use this command to handle it

Parameters:

• action (enum: "accept", "dismiss") (required): Whether to dismiss or accept the dialog
• promptText (string) (optional): Optional prompt text to enter into the dialog.

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hover

Description: Hover over the provided element

Parameters:

• uid (string) (required): The uid of an element on the page from the page content snapshot

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upload_file

Description: Upload a file through a provided element.

Parameters:

• filePath (string) (required): The local path of the file to upload
• uid (string) (required): The uid of the file input element or an element that will open file chooser on the page from the page content snapshot

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Navigation automation

close_page

Description: Closes the page by its index. The last open page cannot be closed.

Parameters:

• pageIdx (number) (required): The index of the page to close. Call list_pages to list pages.

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list_pages

Description: Get a list of pages open in the browser.

Parameters: None

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navigate_page

Description: Navigates the currently selected page to a URL.

Parameters:

• timeout (integer) (optional): Maximum wait time in milliseconds. If set to 0, the default timeout will be used.
• url (string) (required): URL to navigate the page to

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navigate_page_history

Description: Navigates the currently selected page.

Parameters:

• navigate (enum: "back", "forward") (required): Whether to navigate back or navigate forward in the selected pages history
• timeout (integer) (optional): Maximum wait time in milliseconds. If set to 0, the default timeout will be used.

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new_page

Description: Creates a new page

Parameters:

• timeout (integer) (optional): Maximum wait time in milliseconds. If set to 0, the default timeout will be used.
• url (string) (required): URL to load in a new page.

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select_page

Description: Select a page as a context for future tool calls.

Parameters:

• pageIdx (number) (required): The index of the page to select. Call list_pages to list pages.

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wait_for

Description: Wait for the specified text to appear on the selected page.

Parameters:

• text (string) (required): Text to appear on the page
• timeout (integer) (optional): Maximum wait time in milliseconds. If set to 0, the default timeout will be used.

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Emulation

emulate_cpu

Description: Emulates CPU throttling by slowing down the selected page's execution.

Parameters:

• throttlingRate (number) (required): The CPU throttling rate representing the slowdown factor 1-20x. Set the rate to 1 to disable throttling

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emulate_network

Description: Emulates network conditions such as throttling or offline mode on the selected page.

Parameters:

• throttlingOption (enum: "No emulation", "Offline", "Slow 3G", "Fast 3G", "Slow 4G", "Fast 4G") (required): The network throttling option to emulate. Available throttling options are: No emulation, Offline, Slow 3G, Fast 3G, Slow 4G, Fast 4G. Set to "No emulation" to disable. Set to "Offline" to simulate offline network conditions.

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resize_page

Description: Resizes the selected page's window so that the page has specified dimension

Parameters:

• height (number) (required): Page height
• width (number) (required): Page width

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Performance

performance_analyze_insight

Description: Provides more detailed information on a specific Performance Insight that was highlighted in the results of a trace recording.

Parameters:

• insightName (string) (required): The name of the Insight you want more information on. For example: "DocumentLatency" or "LCPBreakdown"

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performance_start_trace

Description: Starts a performance trace recording on the selected page. This can be used to look for performance problems and insights to improve the performance of the page. It will also report Core Web Vital (CWV) scores for the page.

Parameters:

• autoStop (boolean) (required): Determines if the trace recording should be automatically stopped.
• reload (boolean) (required): Determines if, once tracing has started, the page should be automatically reloaded.

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performance_stop_trace

Description: Stops the active performance trace recording on the selected page.

Parameters: None

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Network

get_network_request

Description: Gets a network request by URL. You can get all requests by calling list_network_requests.

Parameters:

• reqid (number) (required): The reqid of a request on the page from the listed network requests

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list_network_requests

Description: List all requests for the currently selected page since the last navigation.

Parameters:

• pageIdx (integer) (optional): Page number to return (0-based). When omitted, returns the first page.
• pageSize (integer) (optional): Maximum number of requests to return. When omitted, returns all requests.
• resourceTypes (array) (optional): Filter requests to only return requests of the specified resource types. When omitted or empty, returns all requests.

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Debugging

evaluate_script

Description: Evaluate a JavaScript function inside the currently selected page. Returns the response as JSON so returned values have to JSON-serializable.

Parameters:

• args (array) (optional): An optional list of arguments to pass to the function.
• function (string) (required): A JavaScript function declaration to be executed by the tool in the currently selected page. Example without arguments: () => { return document.title } or async () => { return await fetch("example.com") }. Example with arguments: (el) => { return el.innerText; }

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list_console_messages

Description: List all console messages for the currently selected page since the last navigation.

Parameters:

• pageIdx (integer) (optional): Page number to return (0-based). When omitted, returns the first page.
• pageSize (integer) (optional): Maximum number of messages to return. When omitted, returns all requests.
• types (array) (optional): Filter messages to only return messages of the specified resource types. When omitted or empty, returns all messages.

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take_screenshot

Description: Take a screenshot of the page or element.

Parameters:

• filePath (string) (optional): The absolute path, or a path relative to the current working directory, to save the screenshot to instead of attaching it to the response.
• format (enum: "png", "jpeg", "webp") (optional): Type of format to save the screenshot as. Default is "png"
• fullPage (boolean) (optional): If set to true takes a screenshot of the full page instead of the currently visible viewport. Incompatible with uid.
• quality (number) (optional): Compression quality for JPEG and WebP formats (0-100). Higher values mean better quality but larger file sizes. Ignored for PNG format.
• uid (string) (optional): The uid of an element on the page from the page content snapshot. If omitted takes a pages screenshot.

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take_snapshot

Description: Take a text snapshot of the currently selected page based on the a11y tree. The snapshot lists page elements along with a unique identifier (uid). Always use the latest snapshot. Prefer taking a snapshot over taking a screenshot.

Parameters:

• verbose (boolean) (optional): Whether to include all possible information available in the full a11y tree. Default is false.

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