[BUG] claude mcp get fails for plugin-namespaced MCP servers

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?

claude mcp list shows plugin-contributed MCP servers with a namespaced format (plugin:<marketplace>:<name>), but claude mcp get cannot retrieve them — even when passing the exact name shown by mcp list.

What Should Happen?

claude mcp get plugin:portal-plugin:portal should return the server config, since that name is reported by mcp list as a configured server.

Error Messages/Logs

$ claude mcp get portal
No MCP server found with name: "portal". Configured servers: ..., plugin:portal-plugin:portal, ...

$ claude mcp get plugin:portal-plugin:portal
No MCP server found with name: "plugin:portal-plugin:portal". Configured servers: ..., plugin:portal-plugin:portal, ...

Steps to Reproduce

1. Install a plugin that registers an MCP server (e.g. portal-plugin)
2. Run claude mcp list — the server appears as plugin:portal-plugin:portal
3. Run claude mcp get portal → fails
4. Run claude mcp get plugin:portal-plugin:portal → also fails, despite being the exact string from step 2

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.126 (Claude Code)

Platform

AWS Bedrock

Operating System

macOS

Terminal/Shell

iTerm2

Additional Information

_No response_

❯ claude mcp get plugin:portal-plugin:portal
plugin:portal-plugin:portal:
  Scope: Dynamic config (from command line)
  Status: ✔ Connected
  Type: http
  URL: https://portal.example.com/api/mcp-actions/v1
  Headers:
    Authorization: [REDACTED]

❯ claude --version
2.1.187 (Claude Code)