redirect error prints to stderr to avoid corrupting MCP stdio transport

[MatthewKhouzam]

What it does

Removes STDout to allow mcps to work

How to test

Run it.

Follow-ups

Will add a flag for stdout.

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the instructions in this template

Summary by CodeRabbit

• Refactor
  • Enhanced error message handling in client operations to properly route errors to standard error stream, improving compatibility with system logging and monitoring tools.

[coderabbitai]

📝 Walkthrough

Walkthrough

The PR adds a sys import and redirects error messages in multiple TspClient methods from standard output to standard error by updating print() calls to include file=sys.stderr, without altering request/response parsing or return control flow.

Changes

Error Output Redirection

Layer / File(s)	Summary
Redirect error messages to stderr tsp/tsp_client.py	Adds sys import and updates HTTP error-handling print() statements across all TspClient methods to write to stderr instead of stdout while preserving error message content and control flow.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

Poem

🐰 In stderr's garden, errors now flow,
Where warnings belong, away from the show,
With sys in hand and messages bright,
TspClient speaks truth on stderr's right!

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and specifically summarizes the main change: redirecting error prints to stderr instead of stdout to avoid corrupting MCP stdio transport. It matches the core purpose of the PR.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

🧹 Nitpick comments (2)

tsp/tsp_client.py (2)

186-186: ⚡ Quick win

Misleading error message.

The error message says "get trace failed" but this is in the fetch_experiment method. Since you're already modifying this line, consider correcting the message to "get experiment failed".

📝 Proposed fix for error message clarity

-            print("get trace failed: {0}".format(response.status_code), file=sys.stderr)
+            print("get experiment failed: {0}".format(response.status_code), file=sys.stderr)

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@tsp/tsp_client.py` at line 186, In the fetch_experiment function update the
stderr print so the error text correctly reflects the operation: change the
message from "get trace failed" to "get experiment failed" while keeping the
status code (response.status_code) and file=sys.stderr intact so the log remains
informative.

---

667-667: ⚡ Quick win

Copy-paste error in error message.

The error message says "post extension failed" but this is in the delete_configuration method. Since you're already modifying this line, consider correcting the message to "delete configuration failed".

📝 Proposed fix for error message clarity

-            print("post extension failed: {0}".format(response.status_code), file=sys.stderr)
+            print("delete configuration failed: {0}".format(response.status_code), file=sys.stderr)

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@tsp/tsp_client.py` at line 667, The error log in delete_configuration
mistakenly says "post extension failed"; update the message in the
delete_configuration method to accurately reflect the operation by changing the
printed string to "delete configuration failed" (keep including the
response.status_code as before) so the print call correctly reads that the
delete configuration request failed; locate the print in delete_configuration
and replace the misleading text only.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@tsp/tsp_client.py`:
- Line 186: In the fetch_experiment function update the stderr print so the
error text correctly reflects the operation: change the message from "get trace
failed" to "get experiment failed" while keeping the status code
(response.status_code) and file=sys.stderr intact so the log remains
informative.
- Line 667: The error log in delete_configuration mistakenly says "post
extension failed"; update the message in the delete_configuration method to
accurately reflect the operation by changing the printed string to "delete
configuration failed" (keep including the response.status_code as before) so the
print call correctly reads that the delete configuration request failed; locate
the print in delete_configuration and replace the misleading text only.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: e3701371-fc9e-419b-98f4-4fca5a432074

📥 Commits

Reviewing files that changed from the base of the PR and between 6eb49d6 and d5a9e5e.

📒 Files selected for processing (1)

• tsp/tsp_client.py

[arfio]

I did not see any other places where this change was required, so this change looks good to me!