chrome-devtools-mcp fails in VS Code Copilot: "Invalid URL" then exit code 1

6 answers

• Best answerAgentArmorHQ teamTeam4d ago

  Status: the issue is closed, but the thread does not name a fixed release, and a user still hit the same failure in April 2026 with chrome-devtools-mcp@0.21.0, so treat this as a workaround rather than a confirmed fix. The maintainer's hypothesis (comments 7 and 9), never confirmed and unreproducible by them: VS Code injects null/empty/invalid values for ${input:...} placeholders into the server args, and an empty URL produces Invalid URL.

  The workaround that worked for two users is to stop using inputs placeholders for the Chrome DevTools args. Remove the four input definitions (browser_url, headless, isolated, chrome_channel) from mcp.json and use a minimal server config:

  jsonCopy to clipboard

  {
    "servers": {
      "chromedevtools/chrome-devtools-mcp": {
        "type": "stdio",
        "command": "npx",
        "args": ["chrome-devtools-mcp@latest"]
      }
    }
  }
  

  Then quit Chrome completely and restart VS Code. One user reported this worked on macOS 26 (comment 10). Another user uninstalled the gallery/store version and added literal args in mcp.json — --channel=stable, --headless=false, --isolated=false, plus --chromePath=E:\Program Files\Google\Chrome\Application\chrome.exe — which started the server (comment 8, OS not stated). If you need custom options, pass them as literal args instead of ${input:...} placeholders, e.g. --browser_url=http://localhost:5173 (comment 10).

  A later user (comment 11) still got the failure with chrome-devtools-mcp@0.21.0 and Chrome opening with a blank URL, so this is not universal. As general advice: avoid promptString inputs for MCP server args until the server tolerates empty values.

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• AgentArmorHQ teamTeam4d ago

  What @Entretoize tried on GitHub (Worked)

  Uninstalled the store/gallery version and manually added a config in mcp.json using literal args only (--channel=stable, --chromePath with a Windows-style Chrome path, --headless=false, --isolated=false). The server started successfully.

  Source: https://github.com/ChromeDevTools/chrome-devtools-mcp/issues/264#issuecomment-3375932622 (opens external site) ↗

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• AgentArmorHQ teamTeam4d ago

  What @dotZak tried on GitHub (Worked)

  Removed the four chrome-devtools input definitions (browser_url, headless, isolated, chrome_channel), kept args to just ["chrome-devtools-mcp@latest"], quit Chrome and restarted VS Code. Worked on macOS 26. A variant with literal args (--browser_url=http://localhost:5173, --channel=stable, --headless=false, --isolated=false) also worked.

  Source: https://github.com/ChromeDevTools/chrome-devtools-mcp/issues/264#issuecomment-3376018300 (opens external site) ↗

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• AgentArmorHQ teamTeam4d ago

  What @sebastianbenz tried on GitHub (Outcome unclear)

  Maintainer suggested trying only the default configuration with no additional parameters; the maintainer could not reproduce the issue and asked how the VS Code input-prompt dialog is triggered.

  Source: https://github.com/ChromeDevTools/chrome-devtools-mcp/issues/264#issuecomment-3375884761 (opens external site) ↗

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• AgentArmorHQ teamTeam4d ago

  What @shaojun tried on GitHub (Didn't work)

  Config with chrome-devtools-mcp@0.21.0 pinned via --registry https://registry.npmjs.org (opens external site) ↗ and empty inputs: still failed, with Chrome opening a blank URL.

  Source: https://github.com/ChromeDevTools/chrome-devtools-mcp/issues/264#issuecomment-4220288854 (opens external site) ↗

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• AgentArmorHQ teamTeam4d ago

  What a GitHub user tried on GitHub (Didn't work)

  Starting chrome-devtools-mcp via GitHub Copilot in VS Code Insiders 1.105.0-insider on Windows 10: the server printed its CLI options and "Invalid URL" to stderr, exited with code 1, and the connection state went Starting → Running → Error.

  Source: https://github.com/ChromeDevTools/chrome-devtools-mcp/issues/264 (opens external site) ↗

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