[BUG] big problem!

### Preflight Checklist

- [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) 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?

Title: Session usage drains abnormally fast — 92% consumed within a short conversation

Body:

I'm on the Pro plan using Claude Code (desktop app). My current session hit 92% usage after a relatively short conversation — far less interaction than what 92% should represent.

What happened:

Started a new session that continued from a previous conversation (context compaction/summary was loaded)
Had approximately 10-15 exchanges with a few web searches
Usage jumped to 92% within this short interaction
Estimated burnout: Monday afternoon (session resets at 4:30 AM daily)

Expected behavior:
A conversation of this length should not consume 92% of the daily session limit. Previous sessions with similar or longer interactions consumed significantly less.

Suspected cause:
The session continuation summary from the previous conversation appears to be very large, and combined with project instruction files (CLAUDE.md, etc.), each turn may be processing an excessive amount of context tokens.

Request:
Could my current session usage be reset? The consumption rate seems disproportionate to the actual work done.

Environment:

Plan: Pro
Platform: macOS (Claude Code desktop app)
Date: 2026-09-12

### What Should Happen?

A short conversation (approximately 10-15 exchanges with some web searches) should not consume 92% of the daily session limit. Similar-length conversations in previous sessions used significantly less usage.

### Error Messages/Logs

```shell
No error messages. The issue is visible in the usage dashboard:
- Current session: 92% used
- Session started: continued from a previous conversation (context compaction/summary loaded)
- Interaction count: ~10-15 user messages, ~12 web searches
- Plan: Pro
- Platform: macOS, Claude Code desktop app
- Date: 2026-09-12
```

### Steps to Reproduce

Session usage dropped to 92% after a very short conversation. The session was continued from a previous conversation, which loaded a large context summary. Combined with project instruction files (CLAUDE.md, etc.), the token consumption per turn appears disproportionately high relative to the actual work done. Requesting a usage reset for this session.

### Claude Model

Opus

### Is this a regression?

Yes, this worked in a previous version

### Last Working Version

_No response_

### Claude Code Version

Claude Code 2.1.238

### Platform

Anthropic API

### Operating System

macOS

### Terminal/Shell

Terminal.app (macOS)

### Additional Information

_No response_

No source file, test, or entry point is identified. Start by reviewing the usage dashboard data for the session, then compare the continued-session summary, CLAUDE.md instructions, web-search activity, and Claude Code 2.1.238 context; done means determining whether the 92% consumption is reproducible accounting behavior or a confirmed defect.

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