[Bug] Unexpected model downgrade from claude-3.5-sonnet to claude-opus-4 without warning

Status Open
Reported on v2.1.263
Maintainer reply None cached
Activity 0 comments · opened Sep 6, 2026

Bug Description
I continue to be pushed off of fable 5.1 while working on projects that I recieved cyber approval to work on with low or no restrictions. In some cases I am not even being warned. I have to check / models to catch that I have been pushed to opus 4.8.

Environment Info

  • Platform: linux
  • Terminal: gnome-terminal
  • Version: 2.1.263
  • Feedback ID: 3783cbd3-4116-476f-8417-ec9ebdf366a5

Errors

[{"error":"TelemetrySafeError: task output swap refused (output file identity changed): /tmp/claude-1000/-home-cknox/45490c47-d6b9-4282-baae-b50315b3b4f5/tasks/b58nbbrxl.output\n    at P (/$bunfs/root/chunk-g9271qmg.js:16:10530)\n    at Ft (/$bunfs/root/chunk-g9271qmg.js:16:5281)\n    at async UJ (/$bunfs/root/chunk-g9271qmg.js:16:3083)\n    at async fbn (/$bunfs/root/chunk-g9271qmg.js:15:2187)\n    at async Zan (/$bunfs/root/chunk-9wa0ka8p.js:1209:25045)\n    at async tms (/$bunfs/root/chunk-9wa0ka8p.js:4722:4825)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-09-06T17:54:54.812Z"},{"error":"TelemetrySafeError: task output swap refused (output file identity changed): /tmp/claude-1000/-home-cknox/45490c47-d6b9-4282-baae-b50315b3b4f5/tasks/b58nbbrxl.output\n    at P (/$bunfs/root/chunk-g9271qmg.js:16:10530)\n    at Ft (/$bunfs/root/chunk-g9271qmg.js:16:5281)\n    at async UJ (/$bunfs/root/chunk-g9271qmg.js:16:3083)\n    at async fbn (/$bunfs/root/chunk-g9271qmg.js:15:2187)\n    at async Zan (/$bunfs/root/chunk-9wa0ka8p.js:1209:25045)\n    at async tms (/$bunfs/root/chunk-9wa0ka8p.js:4722:4825)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-09-06T17:54:54.834Z"}]

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