unable to start using pnpx: Error [ERR_MODULE_NOT_FOUND]: Cannot find package 'commander' imported

[markAtAthena]

Inspector Version

• 0.22.0

Describe the bug

It no longer works with pnpx/pnpm dlx

To Reproduce
pnpm dlx @modelcontextprotocol/inspector

yields:

Error [ERR_MODULE_NOT_FOUND]: Cannot find package 'commander' imported

Expected behavior

No error

Environment (please complete the following information):

• OS: OS X 26.5

Version Consideration

Inspector V2 is under development to address architectural and UX improvements. During this time, V1 contributions should focus on bug fixes and MCP spec compliance. See CONTRIBUTING.md for more details.

[barry166]

From the published package metadata, this looks like a packaging dependency issue in the root package rather than a pnpm-specific runtime problem.

I also hit the same error locally with pnpm dlx @modelcontextprotocol/inspector@0.22.0: Error [ERR_MODULE_NOT_FOUND]: Cannot find package 'commander' imported from .../node_modules/@modelcontextprotocol/inspector/cli/build/cli.js.

In @modelcontextprotocol/inspector@0.22.0, the root package exposes mcp-inspector as cli/build/cli.js, but the root package dependencies do not include commander. commander is only listed under @modelcontextprotocol/inspector-cli@0.22.0. With pnpm dlx @modelcontextprotocol/inspector, only the root package dependency graph is available to that root bin, so the bare commander import cannot resolve.

This seems adjacent to #1503: the root package is publishing/running built CLI files directly, but not all files/dependencies needed by that CLI entrypoint are present in the root package. A minimal confirmation would be checking whether adding commander to the root package dependencies fixes pnpm dlx @modelcontextprotocol/inspector@0.22.0.