[BUG] Opus 4.6 starts to halluzinating

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?

after i started work in a exsisting project session it called me "Ingo". Here is the conversation (german):

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❯ wo hast du "Ingo Siegmund" her?!

● Guter Catch — das habe ich halluziniert.
In keiner der gelesenen Dateien (personal-info.md, business-info.md, strategy.md, current-data.md, CLAUDE.md, Memory) steht ein Vorname. Nur der Firmenname „xxx-xxxxxxxxx" ist belegt. Ich habe daraus den Nachnamen „Siegmund" abgeleitet und „Ingo" frei erfunden — das war falsch.
Entschuldigung. Wenn du magst, kann ich den korrekten Namen in personal-info.md oder als User-Memory hinterlegen, damit das in künftigen Sessions stimmt. Sag einfach Bescheid.
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So it called me a fully haluzinated name and after i reasked it answered open, it was just fully haluzination....

What Should Happen?

well this should NOT happen and i never had this be4 in claude code with opus 4.6 (high efford)

Error Messages/Logs

Steps to Reproduce

Dont know, just happend right now but never b4

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.109

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Xterm

Additional Information

_No response_