fix: claude desktop msix installed path

[Addison (addison-adler)]

Summary

On Windows, Settings → MCP Server shows Claude Desktop as not installed, so Roku Dev Studio can't be added to it. macOS and Linux aren't affected.

Claude's own Windows installer installs it as an MSIX package, which keeps its config somewhere other than the path we check.

Context

MSIX-packaged apps have their %APPDATA% redirected into %LOCALAPPDATA%\Packages\<name>_<publisherHash>\LocalCache\Roaming\.

• Claude Desktop reads …\Packages\Claude_<hash>\LocalCache\Roaming\Claude\claude_desktop_config.json and never reads %APPDATA%\Claude\ (anthropics/claude-code#25579, #26073).
• Detection failed: none of our Windows install candidates exist for an MSIX install.
• The config path was wrong too: even if detection passed, the entry would have gone to %APPDATA%\Claude\, which Claude never reads.
• This isn't limited to the Microsoft Store: Claude's direct-download installer also installs an MSIX package (SignatureKind: Developer).

Changes

• Add findMsixPackageDir, which finds %LOCALAPPDATA%\Packages\<name>_* by name prefix.
  • The per-publisher hash isn't hard-coded.
• Add the Claude package's config folder to Claude's Windows install candidates.
• Point Claude's Windows config path at the package location when it exists.
  • Falls back to %APPDATA%\Claude\ otherwise.
  • The new lookup only runs on the Windows code paths; macOS/Linux are unchanged.

Observations

• ChatGPT Desktop is also distributed as an MSIX package (Microsoft Store), so it may have the same problem.
  • Not changed here: its package name prefix, and whether it reads chatgpt_mcp_config.json, is unverified. I don't have ChatGPT Desktop installed to test that.
  • Once confirmed on a machine with ChatGPT installed, findMsixPackageDir makes the fix a few lines.
• Cursor, Windsurf, VSCodium, and VS Code are unaffected.
  • They install with standard installers rather than MSIX.
  • Cursor's and Windsurf's configs also live in the home folder, outside %APPDATA%.

Test Steps

Tip

Reproduces only when Claude Desktop was installed as an MSIX package, which is how claude.ai's Windows installer installs it. Check with Get-AppxPackage Claude in PowerShell. A dev build (npm start) is enough to test.

1. On Windows, with Claude Desktop installed, open Roku Dev Studio → Settings → MCP Server.
   • Without this fix: Claude Desktop shows as not installed and can't be toggled.
   • With this fix: Claude Desktop shows as installed.
2. Toggle Claude Desktop on and click Save.
   • Without this fix: not possible (see step 1).
   • With this fix: %LOCALAPPDATA%\Packages\Claude_<hash>\LocalCache\Roaming\Claude\claude_desktop_config.json gains a roku-dev-studio entry under mcpServers, and existing entries are preserved.
3. Restart Claude Desktop.
   • With this fix: the roku-dev-studio server appears in Claude's connectors and tools.

[Hareendra Donapati (hdonapati)]

Thanks for this fix too Addison (@addison-adler) - even if I had a chance to test on Windows, this scenario would have been a miss.