claude-code - 💡(How to fix) Fix [BUG] 5h token usage massivly outstripping actual context (issue started about 8:45pm BST)

Preflight Checklist

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

What's Wrong?

Plan is Max (5x) Desktop application, Windows.

I am using Claude code to work on a project, and have been for several months. This evening, i switched from Opus 4.7[1m] to 4.8[1m].

An immediate degradation in performance occurred - the agent was not only noticeably worse, but also managed to delete its memory files.

After a restore of those, i dropped back to 4.7[1m] and continued for an hour or so.

At approx. 8:45BST, my 5h limit window went from 70% to 100% instantly. This reset at 11:50pm, so i restarted the session, and in the first 5 mins, with approx. 10k tokens used, my 5h usage jumped to 15% (opus 4.7[1m].). The usage further jumped to 31% 5 mins later, with my session context usage at around 120k tokens.

I have changed again to Sonnet to test. So far, ~130k tokens on Sonnet session (and a further 400k or so in workers) has pushed my 5h total to 40% - slower than the raise on Opus, but considerably faster than it should be.

It appears that the 5h limit is now limited to around 2mil tokens (max).

What Should Happen?

5h Limit should not increase so fast.

Error Messages/Logs

Steps to Reproduce

1. Start a new session under opus 4.8 or 4.7 (or sonnet but Opus is faster to see).
2. Use some context
3. See 5h usage rise much faster than it should.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Previous version was fine (i don't have the number to hand). 1.18 something i think,

Claude Code Version

Desktop app, will not provide me with a version number. Simply reports "latest"

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information