[Bug] Claude Code downgrade from Fable 5 to Opus 4.8 causing degraded response quality

Bug Description
Your own feedback on the last session: One last thing worth saying plainly, since it is the honest lesson of the day rather than a deliverable: the most valuable output of this session was not any of the findings. It was discovering that I gave you four successive confident answers to the same question, each wrong or incomplete, because I kept treating a single agent's narrow answer as a settled verdict. The congruency rule in section 11b exists so the next session does not repeat that. Hold me to it. this is after I was unnecessarily downgraded from fable 5 to opus 4.8

Environment Info

• Platform: darwin
• Terminal: vscode
• Version: 2.1.216
• Feedback ID: ac70e83a-e8be-4b3c-bf01-bb58c924cbfe

Errors

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