bugfix: fix npx @modelcontextprotoco/inspector failing on main
#681
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This fixes the regression introduced in dc5fa6a where empty strings were passed as arguments when no command or args were provided, causing parseArgs to fail with "Unexpected argument ''" error. The spread operator approach is more idiomatic and avoids creating empty strings that need to be filtered out.
🎭 Playwright E2E Test Results✅ 15 passed Details15 tests across 2 suites 📊 View Detailed HTML Report (download artifacts) |
felixweinberger
changed the title
npx @modelcontextprotoco/inspector fails on master
felixweinberger
changed the title
npx @modelcontextprotoco/inspector fails on masternpx @modelcontextprotoco/inspector failing on main
|
Found this as I was trying to address comments on #661 and in testing found that dc5fa6a (cc: @richardkmichael as FYI) wasn't handling the case when there are no command line arguments. We end up passing |
olaservo
approved these changes
Aug 5, 2025
|
@felixweinberger Thank you! I was hasty in the simplification to strings. 😓 I'll add a test. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Summary
This fixes the regression introduced in dc5fa6a where
npx .(without any arguments) fails with:Problem
Commit dc5fa6a changed the argument passing from using spread syntax to directly including empty strings when no command/args are provided. The
parseArgsfunction in the server interprets these empty strings as unexpected positional arguments.Solution
Reverted to using the spread operator approach that was used before dc5fa6a. This is more idiomatic and avoids creating empty strings that would need to be filtered out.
Test plan
npx .now starts without the parseArgs errornpx . command argsstill works correctly