feat: support logging to stderr in Jupyter Notebook environments (#156) #1707
+763
−58
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
- Add _is_jupyter_notebook() to detect Jupyter/IPython environments - Add _print_stderr() to format stderr with HTML in Jupyter (red color) - Add async _stderr_reader() to capture and display stderr - Pipe stderr (subprocess.PIPE) instead of redirecting to file - Update Windows process creation to support piped stderr - Extract stdout/stdin/stderr readers as module-level functions This enables server stderr output to be visible in Jupyter notebooks, addressing issue modelcontextprotocol#156. Fixes modelcontextprotocol#156
dgenio
force-pushed
the
feature/156-jupyter-stderr-clean
branch
14 times, most recently
from
2239072 to
66c2ca9
Compare
- Test Jupyter environment detection (with/without IPython) - Test stderr printing in Jupyter and non-Jupyter environments - Test IPython display fallback when display fails - Test stderr capture and piping - Test stderr reader exception handling - Test empty line filtering and final buffer handling - Test process without stderr stream Achieves 100% code coverage for the new functionality.
dgenio
force-pushed
the
feature/156-jupyter-stderr-clean
branch
from
66c2ca9 to
4e6bda4
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
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Outdated suggestions cannot be applied.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
Fixes #156 - Adds support for displaying stderr output in Jupyter Notebook environments.
Changes
IPython.get_ipython()FallbackProcessto wrap stderr in async-compatible streamsDesign Decisions
errlogparameter is kept but behavior adapts based on environmentTesting
Behavior
errlogstream (defaults tosys.stderr)This enables proper debugging of MCP servers in Jupyter notebook environments, addressing the issue where server crashes or command errors were invisible.