npx @modelcontextprotocol/inspector fails on 2.10.0: "could not determine executable to run" #2651

Problem

npx @modelcontextprotocol/inspector — the documented way to run the Inspector — fails on 2.10.0:

$ npx -y @modelcontextprotocol/inspector@latest
npm error could not determine executable to run

Cause

2.10.0 added a second bin, mcpdo, next to mcp-inspector. npm's npx/npm exec picks the bin to run with libnpmexec's getBinFromManifest:

1. if every bin points at the same file, run it (true through 2.9.0: only mcp-inspector);
2. else run the bin named after the package's unscoped name — inspector — which doesn't exist;
3. else fail with "could not determine executable to run".

pack:verify and the smokes invoke the installed bin by name (node_modules/.bin/mcp-inspector), so none of them exercises npm's default-bin resolution and the regression shipped green.

Workaround

npx -y -p @modelcontextprotocol/inspector@2.10.0 mcp-inspector

Fix

• Add an inspector bin alias to the root package.json, pointing at the launcher, so rule 2 resolves to it. mcpdo stays reachable via npx -p @modelcontextprotocol/inspector mcpdo.
• Guard it: an offline test:scripts check (runs in validate:guards, so CI) that the root manifest's default bin, resolved by npm's rule, is the launcher; and a pack:verify step that runs the installed tarball via npm exec @modelcontextprotocol/inspector rather than by bin name.
• Release 2.10.1. Meanwhile latest is moved back to 2.9.0 and 2.10.0 deprecated.