[BUG] GitLab MCP plugin fails to reconnect - "Failed to reconnect to plugin:gitlab:gitlab"

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?

The built-in GitLab MCP plugin (gitlab@claude-plugins-official) consistently fails to connect with the error "Failed to reconnect to plugin:gitlab:gitlab". The GitLab API is accessible and the token is valid.

Environment:

• Claude Code version: 2.1.2
• OS: macOS Darwin 25.1.0
• Node.js: v22.3.0
• GitLab: gitlab.com (cloud)

Debugging Done:

• Verified GITLAB_TOKEN is set and valid (direct API call returns HTTP 200):

curl -s -H "PRIVATE-TOKEN: $GITLAB_TOKEN" "https://gitlab.com/api/v4/user"

• Reinstalled Claude Code
• Toggled plugin on/off
• Updated to latest version

Workaround Attempted:
Adding GitLab as standalone HTTP MCP server:
claude mcp add --transport http gitlab-standalone "https://gitlab.com/api/v4/mcp"

Related Issues:

• Similar MCP reconnection failures reported: #16107, #1611, #11175

What Should Happen?

Plugin connects successfully to GitLab MCP server.

Actual Behavior:

• Connection fails despite valid credentials.

Error Messages/Logs

Failed to reconnect to plugin:gitlab:gitlab

Steps to Reproduce

1. Enable the GitLab plugin: claude config set enabledPlugins.gitlab@claude-plugins-official true
2. Set GITLAB_TOKEN environment variable with a valid PAT
3. Start Claude Code
4. Run /mcp
5. Observe: "Failed to reconnect to plugin:gitlab:gitlab"

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.2

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Possible Cause:

• GitLab's MCP server uses protocol version 2025-06-18 (per https://docs.gitlab.com/user/gitlab_duo/model_context_protocol/mcp_server_troubleshooting/). The built-in plugin may not support this protocol version.