Mythos and Fable are the same cost, aren’t they?

Agreed. I was trying to get it to review some auth refactoring in my app recently, and it appeared to find some vulnerabilities. as it was aggregating the results it was flagged and restarted the whole process with Opus 4.8 and all of my usage credits were gone.

Anthropic told me to use their `security-review` tool - as this was the exact scenario the tool is for - and it still got flagged.

Weird. I'm using it to do a bunch of work on something that manages security rules, with a bunch of sample data with spooky scary fixtures all over with "Mimikatz" and "CobaltStrike Beacon" and "Crowdstrike EDR" type stuff everywhere, including work to harden my system, and I've never been downgraded.

I never actually managed to use fable successfully even once on a pretty standard mvc/microservice app.. It would always find the endpoint permission checks and revert to opus 4.8.

I also had glm 5.3 flash fix an issue that opus 5 could not solve. glm took 4 times as long and a sub-agent tried to cheat (sleep; echo ...), but in the end it actually solved the issue. opus 5 never figured it out.

I think the safeguards might be cooking the anthropic models.

I've been testing Fable 5.1 for about 6 hours between last night and this morning and it's performing pretty good overall, including tackling a previous IT sec audit I had ticketed, and completely analysing the codebase looking for vulnerabilities, generating a comprehensive report and splitting it into tickets. So far so good on that front.