[Bug] Anthropic API Error: Messages consistently flagged across all models

**Bug Description**
On every message over Claude Code, I am getting flagged. None of the models are working. None of the Fable or Opus models are working. I am just throwing on the Haiku Even after paying for max subscription and more API usage, I am not getting what I have paid for.

**Environment Info**
- Platform: darwin
- Terminal: Apple_Terminal
- Version: 2.1.258
- Feedback ID: 09cb949c-d522-4572-8f3a-d2788e1cb3ce

**Errors**
```json
[API Error: Fable 5.1's safeguards flagged this message (https://www.anthropic.com/legal/aup). Our intentionally broad safeguards allow us to deliver more capabilities faster, but can sometimes flag
legitimate coding, cybersecurity, and biology tasks. Claude Code can't respond to this message with Fable 5.1.

Double press esc to edit your last message, or try a different model with /model.

Send feedback with /feedback or learn more: https://support.claude.com/en/articles/15363606 ]
```

Start by reproducing the report with Claude Code 2.1.258 on darwin using the affected models, and use feedback ID 09cb949c-d522-4572-8f3a-d2788e1cb3ce when checking the report. The issue does not name a repository file or test; done would require a minimal reproducible message and an actionable cause or confirmed service-side diagnosis.

索引モデルが issue の本文から書いたものです。