UPSTREAM PR #17174: fix(mcp): complete command captures exit code instead of erroring#41
Open
UPSTREAM PR #17174: fix(mcp): complete command captures exit code instead of erroring#41
Conversation
… (#17173) The MCP server now spawns a separate worker process for nushell evaluation, communicating via unix socket instead of stdio. This isolates external commands from the MCP JSON-RPC transport. Key changes: - Added worker process architecture: parent handles MCP transport, child evaluates code - Worker communicates via unix socket at a temp path based on parent PID - Worker runs with --no-config-file to avoid config interference with error handling - Added integration test that spawns actual worker binary The root cause was that config file loading interfered with how external command errors are handled. Skipping config files ensures clean, predictable behavior. Fixes #17173 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
The nushell project disallows unwrap() via clippy::unwrap_used. Use expect() with a clear message explaining the invariant.
loci-dev
force-pushed
the
main
branch
18 times, most recently
from
da22582 to
3f38f88
Compare
loci-dev
force-pushed
the
main
branch
7 times, most recently
from
64bcc48 to
d0a8c7a
Compare
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Note
Source pull request: nushell/nushell#17174
Summary
This is really jank and I feel there is almost certainly a better way, but it does fix the issue I was having.
Fixes #17173
The MCP server now spawns a separate worker process for nushell evaluation, communicating via unix socket instead of stdio. This isolates external commands from the MCP JSON-RPC transport.
--no-config-file(and apparently needs this or some reason)Stdio::null()) so external commands don't mix with JSON-RPCTest plan
let a = (^ls nonexistent | complete); $anow returns{stdout:"",stderr:"...",exit_code:2}instead of erroring