Bug: Terminal stdout stream silently truncating JSON output to exactly 203 characters during Agent execution

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1

When i am runing “npx” command via the cursor i get a truncated json.

I also compare the same command via terminal and got full json.
after i restart the Cursor IDE(cmd+q) the problem disappear.

i would like to know what is the issue, thanks.

2

Hi there!

We detected that this may be a bug report, so we’ve moved your post to the Bug Reports category.

To help us investigate and fix this faster, could you edit your original post to include the details from the template below?

Bug Report Template - Click to expand

Where does the bug appear (feature/product)?

  • Cursor IDE
  • Cursor CLI
  • Background Agent (GitHub, Slack, Web, Linear)
  • BugBot
  • Somewhere else…

Describe the Bug
A clear and concise description of what the bug is.

Steps to Reproduce
How can you reproduce this bug? We have a much better chance at fixing issues if we can reproduce them!

  1. …
  2. …
  3. …

Expected Behavior
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Screenshots / Screen Recordings
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Operating System

  • Windows 10/11
  • MacOS
  • Linux

Version Information

  • For Cursor IDE: Menu → About Cursor → Copy
  • For Cursor CLI: Run agent about in your terminal
IDE:
Version: 2.xx.x
VSCode Version: 1.105.1
Commit: ......

CLI:
CLI Version 2026.01.17-d239e66

For AI issues: which model did you use?
Model name (e.g., Sonnet 4, Tab…)

For AI issues: add Request ID with privacy disabled
Request ID: f9a7046a-279b-47e5-ab48-6e8dc12daba1
For Background Agent issues, also post the ID: bc-…

Additional Information
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Does this stop you from using Cursor?

  • Yes - Cursor is unusable
  • Sometimes - I can sometimes use Cursor
  • No - Cursor works, but with this issue

The more details you provide, the easier it is for us to reproduce and fix the issue. Thanks!

6

Hey, thanks for the report. This looks like an issue with the agent’s shell session state. The fact that restarting with Cmd+Q fixes it is a pretty typical sign. But to confirm it, I’ll need a bit more info:

  1. Your Cursor version Help > About Cursor > Copy and your OS.
  2. A screenshot showing the agent’s truncated output next to the full output from a normal terminal.
  3. The Request ID for the request where the output got cut off chat menu in the top right > Copy Request ID. If Privacy Mode is on, please turn it off temporarily, otherwise the ID won’t be complete.

A couple quick questions too: does the output always get cut at the same point, or does it vary? And are you running the command in a new agent terminal, or an existing session?

With that info, I can match it against known shell output issues. Let me know.