Uses Chrome DevTools MCP and documentation to troubleshoot connection and target issues. Trigger this skill when list_pages, new_page, or navigate_page fail, or when the server initialization fails.

Troubleshooting Wizard You are acting as a troubleshooting wizard to help the user configure and fix their Chrome DevTools MCP server setup. When this skill is triggered (e.g., because list pages , new page , or navigate page failed, or the server wouldn't start), follow this step by step diagnostic process: Step 1: Find and Read Configuration Your first action should be to locate and read the MCP configuration file. Search for the following files in the user's workspace: .mcp.json , gemini extension.json , .claude/settings.json , .vscode/launch.json , or .gemini/settings.json . If you find a configuration file, read and interpret it to identify potential issues such as: Incorrect arguments or flags. Missing environment variables. Usage of autoConnect in incompatible environments. If you cannot find any of these files, only then should you ask the user to provide their configuration file content. Step 2: Triage Common Connection Errors Before reading documentation or suggesting configuration changes, check if the error message matches one of the following common patterns. Error: Could not find DevToolsActivePort This error is highly specific to the autoConnect feature. It means the MCP server cannot find the file created by a running, debuggable Chrome instance. This is not a generic connection failure. Your primary goal is to guide the user to ensure Chrome is running and properly configured. Do not immediately suggest switching to browserUrl . Follow this exact sequence: 1. Ask the user to confirm that the correct Chrome version (e.g., "Chrome Canary" if the error mentions it) is currently running. 2. If the user confirms it is running, instruct them to enable remote debugging. Be very specific about the URL and the action: "Please open a new tab in Chrome, navigate to chrome://inspect/ remote debugging , and make sure the 'Enable remote debugging' checkbox is checked." 3. Once the user confirms both steps, your only next action should be to call the list pages tool. This is the simplest and safest way to verify if the connection is now successful. Do not retry the original, more complex command yet. 4. If list pages succeeds, the problem is resolved. If it still fails with the same error, then you can proceed to the more advanced steps like suggesting browserUrl or checking for sandboxing issues. Symptom: Server starts but creates a new empty profile If the server starts successfully but list pages returns an empty list or creates a new profile instead of connecting to the existing Chrome instance, check for typos in the arguments. Check for flag typos: For example, autoBronnect instead of autoConnect . Verify the configuration: Ensure the arguments match the expected flags exactly. Symptom: Missing Tools / Only 9 tools available If the server starts successfully but only a limited subset of tools (like list pages , get console message , lighthouse audit , take heapsnapshot ) are available, this is likely because the MCP client is enforcing a read only mode . All tools in chrome devtools mcp are annotated with readOnlyHint: true (for safe, non modifying tools) or readOnlyHint: false (for tools that modify browser state, like emulate , click , navigate page ). To access the full suite of tools, the user must disable read only mode in their MCP client (e.g., by exiting "Plan Mode" in Gemini CLI or adjusting their client's tool safety settings). Symptom: Extension tools are missing or extensions fail to load If the tools related to extensions (like install extension ) are not available, or if the extensions you load are not functioning: 1. Check for the categoryExtensions flag : Ensure this flag is passed in the MCP server configuration to enable the extension category tools. 2. Make sure the MCP server in configured to launch Chrome instead of connecting to an instance : Chrome before 149 is not able to load extensions when connecting to an existing instance ( auto connect , browserUrl ). Other Common Errors Identify other error messages from the failed tool call or the MCP initialization logs: Target closed "Tool not found" (check if they are using slim which only enables navigation and screenshot tools). Missing pageId : Page scoped tools require a pageId argument. Call list pages to find active page IDs. ProtocolError: Network.enable timed out or The socket connection was closed unexpectedly Error [ERR MODULE NOT FOUND]: Cannot find module Any sandboxing or host validation errors. Step 3: Read Known Issues Read the contents of https://github.com/ChromeDevTools/chrome devtools mcp/blob/main/docs/troubleshooting.md to map the error to a known issue. Pay close attention to: Sandboxing restrictions (macOS Seatbelt, Linux containers). WSL requirements. autoConnect handshakes, timeouts, and requirements (requires running Chrome 144+). Step 4: Formulate a Configuration Based on the exact error and the user's environment (OS, MCP client), formulate the correct MCP configuration snippet. Check if they need to: Pass browser url=http://127.0.0.1:9222 instead of autoConnect (e.g. if they are in a sandboxed environment like Claude Desktop). Enable remote debugging in Chrome ( chrome://inspect/ remote debugging ) and accept the connection prompt. Ask the user to verify this is enabled if using autoConnect . Add logFile <absolute path to log file to capture debug logs for analysis. Increase startup timeout ms (e.g. to 20000) if using Codex on Windows. If you are unsure of the user's configuration, ask the user to provide their current MCP server JSON configuration. Step 5: Run Diagnostic Commands If the issue is still unclear, run diagnostic commands to test the server directly: Run npx chrome devtools mcp@latest help to verify the installation and Node.js environment. If you need more information, run DEBUG= npx chrome devtools mcp@latest logFile=/tmp/cdm test.log to capture verbose logs. Analyze the output for errors. Step 6: Check GitHub for Existing Issues If https://github.com/ChromeDevTools/chrome devtools mcp/blob/main/docs/troubleshooting.md does not cover the specific error, check if the gh (GitHub CLI) tool is available in the environment. If so, search the GitHub repository for similar issues: gh issue list repo ChromeDevTools/chrome devtools mcp search "<error snippet " state all Alternatively, you can recommend that the user checks https://github.com/ChromeDevTools/chrome devtools mcp/issues and https://github.com/ChromeDevTools/chrome devtools mcp/discussions for help.