# Muse Spark 1.3 Bug

**URL:** <https://forum.cursor.com/t/muse-spark-1-3-bug/171124>\
**Category:** Bug Reports\
**Created:** [September 9, 2026, 4:17am UTC](https://forum.cursor.com/t/muse-spark-1-3-bug/171124 "2026-09-09T04:17:11Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Steven](https://avatars.discourse-cdn.com/v4/letter/s/94ad74/32.png) [@Steven](https://forum.cursor.com/u/Steven)\
**Post date:** [September 9, 2026, 4:17am UTC](https://forum.cursor.com/t/muse-spark-1-3-bug/171124/1 "2026-09-09T04:17:11Z")

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When using the Muse Spark 1.3 model within an agent, it frequently stops working automatically if the “thinking” process exceeds 11 minutes, failing to execute the file editing operation

In Agent mode with Muse Spark 1.3, a normal coding task is cut off after about 11 minutes. The agent never reaches a write/edit tool call. The chat just stops.  
This does not look like hitting the Other Models usage pool. There is no “usage limit” / “rate limit” banner. The run simply ends after sitting in the thinking/planning phase.  
Muse Spark 1.3 often does not stream a thinking chain

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**Author:** ![system](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/system/32/99069_2.png) [@system](https://forum.cursor.com/u/system)\
**Post date:** [September 9, 2026, 4:17am UTC](https://forum.cursor.com/t/muse-spark-1-3-bug/171124/2 "2026-09-09T04:17:20Z")

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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)?**
> 
> - Editor, Tab & Chat (autocomplete, Composer, in-editor agent)
> - Terminal & commands
> - Models, pricing & API keys (availability, Auto/Max, BYOK/Bedrock)
> - MCP & tools
> - Cloud Agents & Automations ([cursor.com/agents](http://cursor.com/agents), scheduled/event)
> - BugBot & Code Review
> - Cursor CLI
> - Cursor Mobile
> - Remote (SSH / Dev Containers / WSL)
> - Account, billing & login
> - Something 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**  
> What is meant to happen here that isn’t working correctly?
> 
> * * *
> 
> **Screenshots / Screen Recordings**  
> If applicable, attach images or videos (.jpg, .png, .gif, .mp4, .mov)
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> **Operating System**
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> - Windows 10/11
> - MacOS
> - Linux
> 
> * * *
> 
> **Version Information**
> 
> - For Cursor IDE: Menu → About Cursor → Copy
> - For Cursor CLI: Run `agent about` in your terminal
> 
> ```auto
> 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**  
> Add any other context about the problem here.
> 
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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!

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<div class="post-metadata">

**Author:** ![Colin](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/colin/32/90452_2.png) [@Colin](https://forum.cursor.com/u/Colin)\
**Post date:** [September 9, 2026, 1:05pm UTC](https://forum.cursor.com/t/muse-spark-1-3-bug/171124/18 "2026-09-09T13:05:29Z")

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Hi @Steven!

Thanks for the report. I’ve tried to reproduce this, but haven’t been successful so far. If you have any examples of requests that made Muse think for a long time on Max mode, I’d love to try and reproduce them!