[Bug] Unexpected model downgrade to Opus 4.8 due to safeguard flag on legitimate coding tasks

Bug Description
fable was doing a simple merge or sometime is dispatching subagents and got this flag and why to opus 4.8 instead of 5 and why change my model and waste tokens for nothing ● Fable 5's safeguards flagged this message. Our intentionally broad safeguards allow us to deliver more capabilities faster, but can sometimes flag legitimate coding, cybersecurity, and biology tasks. Switched to Opus 4.8. Send feedback with /feedback or learn more

Environment Info

• Platform: win32
• Terminal: windows-terminal
• Version: 2.1.223
• Feedback ID: 469b652c-702f-4407-8c56-1fd9d4b21f3f

Errors

[{"error":"TelemetrySafeError: VirtualMessageList: itemKeys/messages length desync (keys=475 messages=474 range=[409,475))\n    at kQS (B:/~BUN/root/src/entrypoints/cli.js:23006:8181)\n    at Yrm (B:/~BUN/root/src/entrypoints/cli.js:23006:1103)\n    at En (B:/~BUN/root/src/entrypoints/cli.js:2544:21373)\n    at HE (B:/~BUN/root/src/entrypoints/cli.js:2544:40470)\n    at OF (B:/~BUN/root/src/entrypoints/cli.js:2544:51396)\n    at _Fe (B:/~BUN/root/src/entrypoints/cli.js:2544:89068)\n    at yFe (B:/~BUN/root/src/entrypoints/cli.js:2544:88013)\n    at SHe (B:/~BUN/root/src/entrypoints/cli.js:2544:87832)\n    at IN (B:/~BUN/root/src/entrypoints/cli.js:2544:84093)\n    at Ke (B:/~BUN/root/src/entrypoints/cli.js:2544:6664)","timestamp":"2026-08-06T19:34:50.478Z"}]