browserUrl not working

[SherlockHomer]

Description of the bug

2025-10-18 14:40:33.057 [info] Handling CreateClient action
2025-10-18 14:40:33.057 [info] Starting new stdio process with command: npx chrome-devtools-mcp@latest --browserUrl=http://127.0.0.1:9222
2025-10-18 14:40:33.256 [info] Handling CreateClient action
2025-10-18 14:40:33.256 [info] Starting new stdio process with command: npx chrome-devtools-mcp@latest --browserUrl=http://127.0.0.1:9222
2025-10-18 14:40:33.335 [error] (node:17133) Warning: Setting the NODE_TLS_REJECT_UNAUTHORIZED environment variable to '0' makes TLS connections and HTTPS requests insecure by disabling certificate verification.
(Use `node --trace-warnings ...` to show where the warning was created)

2025-10-18 14:40:33.508 [error] (node:17138) Warning: Setting the NODE_TLS_REJECT_UNAUTHORIZED environment variable to '0' makes TLS connections and HTTPS requests insecure by disabling certificate verification.
(Use `node --trace-warnings ...` to show where the warning was created)

2025-10-18 14:40:34.208 [error] Options:
      --version         Show version number  [boolean]
  -u, --browserUrl      Connect to a running Chrome instance using port forwarding. For more details see: https://developer.chrome.com/docs/devtools/remote-debugging/local-server.  [string]
      --headless        Whether to run in headless (no UI) mode.  [boolean] [default: false]
  -e, --executablePath  Path to custom Chrome executable.  [string]
      --isolated        If specified, creates a temporary user-data-dir that is automatically cleaned up after the browser is closed.  [boolean] [default: false]
      --channel         Specify a different Chrome channel that should be used.  [string] [choices: "stable", "canary", "beta", "dev"] [default: "stable"]
      --help            Show help  [boolean]

Examples:
  npx chrome-devtools-mcp@latest --browserUrl http://127.0.0.1:9222  Connect to an existing browser instance
  npx chrome-devtools-mcp@latest --channel beta                      Use Chrome Beta installed on this system
  npx chrome-devtools-mcp@latest --channel canary                    Use Chrome Canary installed on this system
  npx chrome-devtools-mcp@latest --channel dev                       Use Chrome Dev installed on this system
  npx chrome-devtools-mcp@latest --channel stable                    Use stable Chrome installed on this system
  npx chrome-devtools-mcp@latest --logFile /tmp/log.txt              Save logs to a file
  npx chrome-devtools-mcp@latest --help                              Print CLI options

2025-10-18 14:40:34.209 [error] 
Arguments channel and browserUrl are mutually exclusive

2025-10-18 14:40:34.217 [info] Client closed for command
2025-10-18 14:40:34.220 [info] Handling ListOfferings action, server stored: false
2025-10-18 14:40:34.220 [error] No server info found
2025-10-18 14:40:34.222 [info] Handling ListOfferings action, server stored: false
2025-10-18 14:40:34.222 [error] No server info found
2025-10-18 14:40:34.222 [info] Handling ListOfferings action, server stored: false
2025-10-18 14:40:34.222 [error] No server info found
2025-10-18 14:40:34.238 [error] Options:
      --version         Show version number  [boolean]
  -u, --browserUrl      Connect to a running Chrome instance using port forwarding. For more details see: https://developer.chrome.com/docs/devtools/remote-debugging/local-server.  [string]
      --headless        Whether to run in headless (no UI) mode.  [boolean] [default: false]
  -e, --executablePath  Path to custom Chrome executable.  [string]
      --isolated        If specified, creates a temporary user-data-dir that is automatically cleaned up after the browser is closed.  [boolean] [default: false]
      --channel         Specify a different Chrome channel that should be used.  [string] [choices: "stable", "canary", "beta", "dev"] [default: "stable"]
      --help            Show help  [boolean]

Examples:
  npx chrome-devtools-mcp@latest --browserUrl http://127.0.0.1:9222  Connect to an existing browser instance
  npx chrome-devtools-mcp@latest --channel beta                      Use Chrome Beta installed on this system
  npx chrome-devtools-mcp@latest --channel canary                    Use Chrome Canary installed on this system
  npx chrome-devtools-mcp@latest --channel dev                       Use Chrome Dev installed on this system
  npx chrome-devtools-mcp@latest --channel stable                    Use stable Chrome installed on this system
  npx chrome-devtools-mcp@latest --logFile /tmp/log.txt              Save logs to a file
  npx chrome-devtools-mcp@latest --help                              Print CLI options

2025-10-18 14:40:34.238 [error] 

2025-10-18 14:40:34.238 [error] Arguments channel and browserUrl are mutually exclusive

2025-10-18 14:40:34.246 [info] Client closed for command
2025-10-18 14:40:34.248 [info] Handling ListOfferings action, server stored: false
2025-10-18 14:40:34.248 [error] No server info found
2025-10-18 14:40:34.252 [info] Handling ListOfferings action, server stored: false
2025-10-18 14:40:34.252 [error] No server info found
2025-10-18 14:40:34.252 [info] Handling ListOfferings action, server stored: false
2025-10-18 14:40:34.252 [error] No server info found

My MCP config:

"chrome-devtools": {
      "type": "stdio",
      "command": "npx",
      "args": [  
        "chrome-devtools-mcp@latest",
        "--browserUrl=http://127.0.0.1:9222"
      ],
      "env": {}
    }

1. When I remove "--browserUrl=http://127.0.0.1:9222", it worked.
   But I want connect to a running Chrome instance.
   And I have run "/Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --remote-debugging-port=9222 --user-data-dir=/tmp/chrome-profile-stable".

2. When I used "--wsEndpoint=ws://127.0.0.1:9222/devtools/browser/", there is not error on cursor MCP tab. But when I prompted 'open some website'. It didn't connect to a running Chrome Stable instance, the 9222.

Reproduction

No response

Expectation

connect to a running Chrome instance.

MCP configuration

{
 "chrome-devtools": {
      "command": "npx",
      "args": [  
        "chrome-devtools-mcp@latest",
        "--browserUrl=http://127.0.0.1:9222"
      ],
      "env": {}
    }
}

Node version

v22.12.0

Chrome version

Version 141.0.7390.108 (Official Build) (arm64)

Coding agent version

cursor Version: 1.7.52 (Universal) VSCode Version: 1.99.3

Model version

No response

Chat log

No response

Operating system

macOS

Extra checklist

• I want to provide a PR to fix this bug

[OrKoN]

I am not able to reproduce on the latest released version. What is the version that npx chrome-devtools-mcp@latest --version outputs? wsEndpoint only exists on the main branch and was not released to npm yet.

[OrKoN]

Somehow the version you run is not the latest. The latest version should have the following command line args:

[OrKoN]

So please upgrade to the latest version (it seems like either your npx installation for some reason does not check for the latest version or does not download it for some reason, perhaps due to NODE_TLS_REJECT_UNAUTHORIZED being set to 0).

[SherlockHomer]

I got it. This was caused by the old version.
The latest version of the private registry is 0.2.0. It it too old.
Thanks a lot.