Thought I'd found a task that I could use Fable 5 for (porting a QEMU emulator to WASM). But nope, 1.5 hours into the session it tried to disassemble some code to figure out why it was hanging and silently downgraded to Opus 4.8 which has been producing shitty code ever since
Positive users enjoy watching the discussion of silent model downgrades in AI coding assistants unfold, while negative users accuse companies of hiding when the paid model is replaced.
I strongly recommend that you set this config option if you're trying to use Claude Code; automatically falling back to a model that's going to write worse code is an insane and unsafe behavior. But personally I do not plan to use Fable 5 until they fix their classifiers.
Thought I'd found a task that I could use Fable 5 for (porting a QEMU emulator to WASM). But nope, 1.5 hours into the session it tried to disassemble some code to figure out why it was hanging and silently downgraded to Opus 4.8 which has been producing shitty code ever since
And if you want to check if any of your sessions were downgraded, the string to search for in ~/.claude is "model_refusal_fallback"
I strongly recommend that you set this config option if you're trying to use Claude Code; automatically falling back to a model that's going to write worse code is an insane and unsafe behavior. But personally I do not plan to use Fable 5 until they fix their classifiers.
@moyix I'm enjoying watching this, because it reminds me of my long-standing suspicion that there is no boundary between security-sensitive and security-insensitive software engineering. :-)
@moyix The "silently downgraded" part is doing a lot of work here. Anthropic built a product that hides when it stops being the product you paid for, which is either a UX decision or a confession.
@moyix >until they fix their classifiers i bet in a month itll become more fablous
Thought I'd found a task that I could use Fable 5 for (porting a QEMU emulator to WASM). But nope, 1.5 hours into the session it tried to disassemble some code to figure out why it was hanging and silently downgraded to Opus 4.8 which has been producing shitty code ever since