[Bug] Anthropic API Error: Invalid Model Name for Fable

Bug Description
Building a prototype for a sample prototype dashboard. Can't use fable model? false positive! Please help!

Environment Info

• Platform: darwin
• Terminal: iTerm.app
• Version: 2.1.177
• Feedback ID: b9deeec2-4717-448d-b3e9-e158c9735f41

Errors

[{"error":"Error: 404 {\"type\":\"error\",\"error\":{\"type\":\"not_found_error\",\"message\":\"Claude Fable 5 is not available. Please use Opus 4.8. Learn more: https://www.anthropic.com/news/fable-mythos-access\"},\"request_id\":\"req_011CbzSVSLQ4BAcR9nvRqAhs\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:12:67578)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:52:7694)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-06-13T02:05:43.233Z"}]