[BUG] Issue with Atlassian MCP

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

this is from my debugging session. basically my atlassian mcp was working last night but not today after the update.

Environment Information
-----------------------

System:

• OS: Windows 10 (MINGW64_NT-10.0-26100)
• Shell: MSYS/Git Bash (/usr/bin/bash)
• Claude Code Version: 2.0.44
• Node.js: v22.17.0
• npm: 10.9.2
• mcp-remote version: 0.1.31

Issue Description
-----------------

The Atlassian MCP server fails to connect with the error:

plugin:cs-dev:atlassian: npx -y mcp-remote https://mcp.atlassian.com/v1/sse - ✗ Failed to connect

Root Cause
----------

The mcp-remote package crashes during OAuth authentication coordination:

Fatal error: TypeError: Cannot read properties of null (reading 'port')
at coordinateAuth (file:///C:/Users/jason.edwards/AppData/Local/npm-cache/_npx/705d23756ff7dacc/node_modules/mcp-remote/dist/chunk-WSHBHZXM.js:14600:30)
at Object.initializeAuth (file:///C:/Users/jason.edwards/AppData/Local/npm-cache/_npx/705d23756ff7dacc/node_modules/mcp-remote/dist/chunk-WSHBHZXM.js:14545:25)
at authInitializer (file:///C:/Users/jason.edwards/AppData/Local/npm-cache/_npx/705d23756ff7dacc/node_modules/mcp-remote/dist/proxy.js:128:45)
at connectToRemoteServer (file:///C:/Users/jason.edwards/AppData/Local/npm-cache/_npx/705d23756ff7dacc/node_modules/mcp-remote/dist/chunk-WSHBHZXM.js:13875:58)
at async runProxy (file:///C:/Users/jason.edwards/AppData/Local/npm-cache/_npx/705d23756ff7dacc/node_modules/mcp-remote/dist/proxy.js:140:29)

What Works
----------

✓ Network connectivity to https://mcp.atlassian.com (confirmed via curl)
✓ SSE endpoint responds correctly (returns 401 requiring auth, as expected)
✓ OAuth browser window opens successfully
✓ mcp-remote package initializes

What Fails
----------

✗ OAuth callback coordination crashes when trying to read 'port' property from null object
✗ Connection never completes, preventing all Atlassian MCP tools from being available

Reproduction Steps
------------------

Running the following command from MSYS/Git Bash on Windows consistently produces the error after the OAuth browser opens:

npx -y mcp-remote https://mcp.atlassian.com/v1/sse

Full Output:
[120636] Using existing client port: 5598
[120636] [120636] Connecting to remote server: https://mcp.atlassian.com/v1/sse
[120636] Using transport strategy: http-first
[120636]
Please authorize this client by visiting:
https://mcp.atlassian.com/v1/authorize?response_type=code&client_id=AM_z79zM71qWdYq0&code_challenge=qzPUYENNn6ach0En-OLJnH4_zXWTbN5UFDmOOgKybcU&code_challenge_method=S256&redirect_uri=http%3A%2F%2Flocalhost%3A5598%2Foauth%2Fcallback&state=7683ff80-1da3-4dc4-9424-db1edae288d3&scope=openid+email+profile

[120636] Browser opened automatically.
[120636] Authentication required. Initializing auth...
[120636] Initializing auth coordination on-demand
[120636] Fatal error: TypeError: Cannot read properties of null (reading 'port')

Network Connectivity Tests
--------------------------

Test 1 - Main endpoint:
curl -v -L --max-time 10 https://mcp.atlassian.com
Result: HTTP/1.1 404 Not Found (expected - root path not available)
Server: AtlassianEdge

Test 2 - SSE endpoint:
curl -v -L --max-time 10 https://mcp.atlassian.com/v1/sse
Result: HTTP/1.1 401 Unauthorized (expected - requires OAuth)
Response: {"error":"invalid_token","error_description":"Missing or invalid access token"}

What Should Happen?

I was able to authenticate and use the mcp in my plugin prior to this.

Error Messages/Logs

Full Output:
    [120636] Using existing client port: 5598
    [120636] [120636] Connecting to remote server: https://mcp.atlassian.com/v1/sse
    [120636] Using transport strategy: http-first
    [120636]
    Please authorize this client by visiting:
    https://mcp.atlassian.com/v1/authorize?response_type=code&client_id=AM_z79zM71qWdYq0&code_challenge=qzPUYENNn6ach0En-OLJnH4_zXWTbN5UFDmOOgKybcU&code_challenge_method=S256&redirect_uri=http%3A%2F%2Flocalhost%3A5598%2Foauth%2Fcallback&state=7683ff80-1da3-4dc4-9424-db1edae288d3&scope=openid+email+profile

    [120636] Browser opened automatically.
    [120636] Authentication required. Initializing auth...
    [120636] Initializing auth coordination on-demand
    [120636] Fatal error: TypeError: Cannot read properties of null (reading 'port')

Steps to Reproduce

Running the following command from MSYS/Git Bash on Windows consistently produces the error after the OAuth browser opens:

npx -y mcp-remote https://mcp.atlassian.com/v1/sse

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.0.43

Claude Code Version

2.0.44

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

I have tried from windows cmd and the vscode plugin