[BUG] Auto-Compact is not happening in Claude Code Cursor extension like it was before - goes past 100%

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

When in Cursor, on MacOS, using the claude extension in a tabbed view, it used to auto compact at around 88%. Suddenly in the past 2 days (day? 1/12/2026) it is NOT auto compacting at all. It will routinely go past 100%.

Contributing factors: I run several tabs (conversations) at the same time - have done that for months. I often restart Cursor, and then successfully go back to these conversations and they pick up again like a champ. I say that to give full context.

I have not changed any settings. Last version update was yesterday, when this started (now is v2.1.5).

What Should Happen?

Should auto compact at around 88%, not go to 100%.

Error Messages/Logs

None

Steps to Reproduce

Use the current extension based agent in a tab in Cursor on MacOS. Don't compact. Read lots of big context code files and fill up the context. Watch as it goes to 100%.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.4

Claude Code Version

2.1.5

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Cursor

Additional Information

<img width="859" height="194" alt="Image" src="https://github.com/user-attachments/assets/ad2c0336-f869-4b3f-8080-554e1160be11" />

<img width="434" height="157" alt="Image" src="https://github.com/user-attachments/assets/59f7c532-49c5-4100-bf8b-3c419b72a4b5" />