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Opera DevTools MCP

This is a fork of chrome-devtools-mcp (Copyright 2025 Google LLC), extended with Opera Neon AI features.

npm opera-devtools-mcp package

opera-devtools-mcp lets your coding agent (such as Claude, Cursor, or Copilot) control and inspect a live browser. It acts as a Model-Context-Protocol (MCP) server, giving your AI coding assistant access to the full power of DevTools for reliable automation, in-depth debugging, and performance analysis. When connected to Opera Neon, it also exposes Opera's built-in AI capabilities.

Key features

  • Opera Neon AI tools: Interact with Opera's built-in AI directly from your coding agent — chat, perform page actions, generate content, and run research.
  • Get performance insights: Uses Chrome DevTools to record traces and extract actionable performance insights.
  • Advanced browser debugging: Analyze network requests, take screenshots and check browser console messages (with source-mapped stack traces).
  • Reliable automation: Uses puppeteer to automate actions in the browser and automatically wait for action results.

Opera Neon AI tools

These tools are only available when connected to Opera Neon via --browser-url.

Tool Description
opera_chat Send a chat prompt to Opera's built-in AI and return the response.
opera_do Instruct Opera's built-in AI to perform an action on the current page.
opera_make Ask Opera's built-in AI to create or generate content.
opera_research Ask Opera's built-in AI to research a topic. Supports local, one-minute, and deep research modes.

Disclaimers

opera-devtools-mcp exposes content of the browser instance to the MCP clients allowing them to inspect, debug, and modify any data in the browser or DevTools. Avoid sharing sensitive or personal information that you don't want to share with MCP clients.

Performance tools may send trace URLs to the Google CrUX API to fetch real-user experience data. To disable this, run with the --no-performance-crux flag.

Requirements

Getting started

Add the following config to your MCP client:

{
  "mcpServers": {
    "opera-devtools": {
      "command": "npx",
      "args": ["-y", "opera-devtools-mcp@latest"]
    }
  }
}

Note

Using opera-devtools-mcp@latest ensures that your MCP client will always use the latest version of the Opera DevTools MCP server.

Connecting to Opera Neon

To use Opera Neon AI tools, start Opera Neon with remote debugging enabled and connect via --browser-url:

{
  "mcpServers": {
    "opera-devtools": {
      "command": "npx",
      "args": [
        "-y",
        "opera-devtools-mcp@latest",
        "--browser-url=http://127.0.0.1:9222"
      ]
    }
  }
}

Start Opera Neon with the remote debugging port:

# macOS
/Applications/Opera\ Neon.app/Contents/MacOS/Opera\ Neon --remote-debugging-port=9222 --user-data-dir=/tmp/opera-profile

MCP Client configuration

Claude Code
claude mcp add opera-devtools --scope user npx opera-devtools-mcp@latest
Cursor

Go to Cursor Settings -> MCP -> New MCP Server. Use the config provided above.

Copilot / VS Code

Follow the VS Code MCP configuration guide using the standard config from above, or use the CLI:

code --add-mcp '{"name":"opera-devtools","command":"npx","args":["-y","opera-devtools-mcp"],"env":{}}'
Windsurf Follow the configure MCP guide using the standard config from above.
Cline Follow https://docs.cline.bot/mcp/configuring-mcp-servers and use the config provided above.

Your first prompt

Enter the following prompt in your MCP Client to check if everything is working:

Check the performance of https://opera.com

Your MCP client should open the browser and record a performance trace.

Note

The MCP server will start the browser automatically once the MCP client uses a tool that requires a running browser instance. Connecting to the Opera DevTools MCP server on its own will not automatically start the browser.

Tools

If you run into any issues, checkout our troubleshooting guide.

Configuration

The Opera DevTools MCP server supports the following configuration options:

  • --autoConnect/ --auto-connect If specified, automatically connects to a browser (Chrome 144+) running locally from the user data directory identified by the channel param (default channel is stable). Requires the remote debugging server to be started in the Chrome instance via chrome://inspect/#remote-debugging.

    • Type: boolean
    • Default: false
  • --browserUrl/ --browser-url, -u Connect to a running, debuggable Chrome instance (e.g. http://127.0.0.1:9222). For more details see: https://github.com/operasoftware/opera-devtools-mcp#connecting-to-a-running-chrome-instance.

    • Type: string
    • Default: false
  • --wsEndpoint/ --ws-endpoint, -w WebSocket endpoint to connect to a running Chrome instance (e.g., ws://127.0.0.1:9222/devtools/browser/). Alternative to --browserUrl.

    • Type: string
    • Default: false
  • --wsHeaders/ --ws-headers Custom headers for WebSocket connection in JSON format (e.g., '{"Authorization":"Bearer token"}'). Only works with --wsEndpoint.

    • Type: string
    • Default: false
  • --headless Whether to run in headless (no UI) mode.

    • Type: boolean
    • Default: false
  • --executablePath/ --executable-path, -e Path to custom Chrome executable.

    • Type: string
    • Default: false
  • --isolated If specified, creates a temporary user-data-dir that is automatically cleaned up after the browser is closed. Defaults to false.

    • Type: boolean
    • Default: false
  • --userDataDir/ --user-data-dir Path to the user data directory for Chrome. Default is $HOME/.cache/opera-devtools-mcp/chrome-profile$CHANNEL_SUFFIX_IF_NON_STABLE

    • Type: string
    • Default: false
  • --channel Specify a different Chrome channel that should be used. The default is the stable channel version.

    • Type: string
    • Choices: canary, dev, beta, stable
    • Default: false
  • --logFile/ --log-file Path to a file to write debug logs to. Set the env variable DEBUG to * to enable verbose logs. Useful for submitting bug reports.

    • Type: string
    • Default: false
  • --viewport Initial viewport size for the Chrome instances started by the server. For example, 1280x720. In headless mode, max size is 3840x2160px.

    • Type: string
    • Default: false
  • --proxyServer/ --proxy-server Proxy server configuration for Chrome passed as --proxy-server when launching the browser. See https://www.chromium.org/developers/design-documents/network-settings/ for details.

    • Type: string
    • Default: false
  • --acceptInsecureCerts/ --accept-insecure-certs If enabled, ignores errors relative to self-signed and expired certificates. Use with caution.

    • Type: boolean
    • Default: false
  • --experimentalPageIdRouting/ --experimental-page-id-routing Whether to expose pageId on page-scoped tools and route requests by page ID (useful for concurrent agent sessions).

    • Type: boolean
    • Default: false
  • --experimentalDevtools/ --experimental-devtools Whether to enable automation over DevTools targets

    • Type: boolean
    • Default: false
  • --experimentalVision/ --experimental-vision Whether to enable coordinate-based tools such as click_at(x,y). Usually requires a computer-use model able to produce accurate coordinates by looking at screenshots.

    • Type: boolean
    • Default: false
  • --memoryDebugging/ --memory-debugging, -experimentalMemory Whether to enable memory debugging tools.

    • Type: boolean
    • Default: false
  • --experimentalStructuredContent/ --experimental-structured-content Whether to output structured formatted content.

    • Type: boolean
    • Default: false
  • --experimentalIncludeAllPages/ --experimental-include-all-pages Whether to include all kinds of pages such as webviews or background pages as pages.

    • Type: boolean
    • Default: false
  • --experimentalScreencast/ --experimental-screencast Exposes experimental screencast tools (requires ffmpeg). Install ffmpeg https://www.ffmpeg.org/download.html and ensure it is available in the MCP server PATH.

    • Type: boolean
    • Default: false
  • --experimentalFfmpegPath/ --experimental-ffmpeg-path Path to ffmpeg executable for screencast recording.

    • Type: string
    • Default: false
  • --categoryExperimentalWebmcp/ --category-experimental-webmcp Set to true to enable debugging WebMCP tools. Requires Chrome 150+ with the following flag: --enable-features=WebMCP

    • Type: boolean
    • Default: false
  • --chromeArg/ --chrome-arg Additional arguments for Chrome. Only applies when Chrome is launched by opera-devtools-mcp.

    • Type: array
    • Default: false
  • --blockedUrlPattern/ --blocked-url-pattern Restricts browser's network access by blocking specified URL patterns (uses https://urlpattern.spec.whatwg.org/). Silently detaches from targets with blocked URLs upon connection, and blocks runtime requests (including navigations and subresources). Accepts an array of patterns.

    • Type: array
    • Default: false
  • --allowedUrlPattern/ --allowed-url-pattern Restricts browser's network access by allowing only specified URL patterns (uses https://urlpattern.spec.whatwg.org/). Requires Chrome 149+. Silently detaches from targets with unallowed URLs upon connection, and blocks runtime requests (including navigations and subresources). Accepts an array of patterns.

    • Type: array
    • Default: false
  • --ignoreDefaultChromeArg/ --ignore-default-chrome-arg Explicitly disable default arguments for Chrome. Only applies when Chrome is launched by opera-devtools-mcp.

    • Type: array
    • Default: false
  • --categoryEmulation/ --category-emulation Set to false to exclude tools related to emulation.

    • Type: boolean
    • Default: true
  • --categoryPerformance/ --category-performance Set to false to exclude tools related to performance.

    • Type: boolean
    • Default: true
  • --categoryNetwork/ --category-network Set to false to exclude tools related to network.

    • Type: boolean
    • Default: true
  • --categoryExtensions/ --category-extensions Set to true to include tools related to extensions. Note: This feature is currently only supported with a pipe connection. autoConnect, browserUrl, and wsEndpoint are not supported with this feature until 149 will be released.

    • Type: boolean
    • Default: false
  • --categoryExperimentalThirdParty/ --category-experimental-third-party Set to true to enable third-party developer tools exposed by the inspected page itself

    • Type: boolean
    • Default: false
  • --categoryPwa/ --category-pwa Set to true to include tools for automating Progressive Web Apps (install, launch, uninstall, and OS state). This feature is only supported with a pipe connection; autoConnect, browserUrl, and wsEndpoint are not supported.

    • Type: boolean
    • Default: false
  • --performanceCrux/ --performance-crux Set to true to enable sending URLs from performance traces to CrUX API to get field performance data.

    • Type: boolean
    • Default: false
  • --usageStatistics/ --usage-statistics Set to true to opt-in to usage statistics collection. Google collects usage data to improve the tool, handled under the Google Privacy Policy (https://policies.google.com/privacy). This is independent from Chrome browser metrics. Disabled if OPERA_DEVTOOLS_NO_USAGE_STATISTICS or CI env variables are set.

    • Type: boolean
    • Default: false
  • --screenshotFormat/ --screenshot-format Override the default output format used by take_screenshot when the caller does not specify one. JPEG and WebP are ~3-5x smaller than PNG, which helps reduce context size in AI conversations. Unset preserves the existing default ("png").

    • Type: string
    • Choices: jpeg, png, webp
    • Default: false
  • --screenshotQuality/ --screenshot-quality Override the default compression quality (0-100) used by take_screenshot for JPEG and WebP when the caller does not specify one. Lower values mean smaller files. Ignored for PNG. Unset preserves the Puppeteer default.

    • Type: number
    • Default: false
  • --screenshotMaxWidth/ --screenshot-max-width Maximum width in pixels for screenshots. If the captured image is wider, it is downscaled (preserving aspect ratio) before being returned. Reduces context size in AI conversations. Unset means no resize.

    • Type: number
    • Default: false
  • --screenshotMaxHeight/ --screenshot-max-height Maximum height in pixels for screenshots. If the captured image is taller, it is downscaled (preserving aspect ratio) before being returned. Can be combined with --screenshot-max-width; the smaller scale factor wins. Unset means no resize.

    • Type: number
    • Default: false
  • --slim Exposes a "slim" set of 3 tools covering navigation, script execution and screenshots only. Useful for basic browser tasks.

    • Type: boolean
    • Default: false
  • --redactNetworkHeaders/ --redact-network-headers If true, redacts some of the network headers considered sensitive before returning to the client.

    • Type: boolean
    • Default: false
  • --allowUnrestrictedPaths/ --allow-unrestricted-paths If set, disables the default path restriction that applies when the MCP client does not negotiate the roots capability. By default, file-writing tools are restricted to the OS temp directory when no roots are configured. Use this only when connecting a trusted local client that does not implement MCP roots and requires access to paths outside the temp directory.

    • Type: boolean
    • Default: false

Pass them via the args property in the JSON configuration. For example:

{
  "mcpServers": {
    "opera-devtools": {
      "command": "npx",
      "args": [
        "opera-devtools-mcp@latest",
        "--headless=true",
        "--isolated=true"
      ]
    }
  }
}

Connecting via WebSocket with custom headers

{
  "mcpServers": {
    "opera-devtools": {
      "command": "npx",
      "args": [
        "opera-devtools-mcp@latest",
        "--wsEndpoint=ws://127.0.0.1:9222/devtools/browser/<id>",
        "--wsHeaders={\"Authorization\":\"Bearer YOUR_TOKEN\"}"
      ]
    }
  }
}

Concepts

User data directory

opera-devtools-mcp starts a browser instance using the following user data directory:

  • Linux / macOS: $HOME/.cache/chrome-devtools-mcp/chrome-profile-$CHANNEL
  • Windows: %HOMEPATH%/.cache/chrome-devtools-mcp/chrome-profile-$CHANNEL

The user data directory is not cleared between runs. Set the isolated option to true to use a temporary user data dir instead which will be cleared automatically after the browser is closed.

Connecting to a running browser instance

By default, the server will start a new Chrome instance with a dedicated profile. You can instead connect to a running instance via --browser-url:

{
  "mcpServers": {
    "opera-devtools": {
      "command": "npx",
      "args": [
        "opera-devtools-mcp@latest",
        "--browser-url=http://127.0.0.1:9222"
      ]
    }
  }
}

Start the browser with the remote debugging port enabled:

macOS (Chrome)

/Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --remote-debugging-port=9222 --user-data-dir=/tmp/chrome-profile-stable

macOS (Opera Neon)

/Applications/Opera\ Neon.app/Contents/MacOS/Opera\ Neon --remote-debugging-port=9222 --user-data-dir=/tmp/opera-profile

Linux

/usr/bin/google-chrome --remote-debugging-port=9222 --user-data-dir=/tmp/chrome-profile-stable

Windows

"C:\Program Files\Google\Chrome\Application\chrome.exe" --remote-debugging-port=9222 --user-data-dir="%TEMP%\chrome-profile-stable"

Warning

Enabling the remote debugging port opens up a debugging port on the running browser instance. Any application on your machine can connect to this port and control the browser. Make sure that you are not browsing any sensitive websites while the debugging port is open.

Debugging Chrome on Android

Please consult these instructions.

Known limitations

See Troubleshooting.

License

Apache 2.0. See LICENSE and NOTICE.

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