Does this issue occur when all extensions are disabled?: Yes/No

• VS Code Version: Insiders as of 2025-07-24
• OS Version: Windows 11

Steps to Reproduce:

1. Ensure NuGet MCP is enabled with "chat.mcp.assisted.nuget.enabled": true (as of Add experiment flag around NuGet MCP assisted config #257463)
2. Use MCP: Add MCP... from the command palette
3. Select NuGet Package
4. Enter NuGet.Mcp.Server (NuGet team's MCP server)
5. Answer yes to the install prompt

The flow terminates, the server ID is not prompted for. Using the debugger I see the tool loop succeeds (it reads the README and generates MCP client configuration) but the config never makes it into the user/workspace settings. The user vs. workspace settings decision is not prompted.

It also doesn't show the "Thinking" status like npm.

Compare this to npm and the @azure/mcp package, which works great, resulting in a configured MCP in the user settings.