[BUG] Fable 5.1 Burning usage twice in less than an hour doing nothing complicated

### 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?

I have started using Fable 5.1 today to help me build a workflow for literature base, and twice in a row I ran out of the limit in less than 1 hour. I was doing a similar task yesterday with Opus 5, and an even more demanding one, and I never ran into the limits issue. For me, it feels more like a bug than just normal usage limits. I am on **20x Max** plan.

### What Should Happen?

I don't expect Claude to run into a usage limit that fast, especially since I am on the **20x Max** plan.

### Error Messages/Logs

```shell

```

### Steps to Reproduce

Just look on my usage of today.

### Claude Model

Other

### Is this a regression?

I don't know

### Last Working Version

_No response_

### Claude Code Version

2.1.258

### Platform

Anthropic API

### Operating System

macOS

### Terminal/Shell

Terminal.app (macOS)

### Additional Information

_No response_

No files, tests, entry points, logs, or reproducible steps are provided. Start by reviewing the reported usage for today alongside Claude Code version 2.1.258, the Fable 5.1 sessions, and the 20x Max plan; done means establishing whether the usage-limit behavior is reproducible and identifying evidence of unexpected consumption.

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