Fable is Mythos, and it is really good. — Summary & Key Points
TL;DR
Anthropic released 'Fable 5' (Mythos 5), a coding model that crushes benchmarks and builds complex games in hours, but it is expensive, has strict usage limits, and requires 30-day data retention. Despite safety refusals on sensitive topics, it is the most capable coding model available right now, and you should use it to solve problems five times harder than usual while the access window lasts.
Key Quotes
"It's more thorough. It's more willing to cheat. It's harder working. It is smarter."
The argument
Benchmark dominance
Fable 5 crushes benchmarks like SWE-bench Pro (80%) and Frontier Code Diamond (30%) and can build terminal games or Minecraft clones in hours.
Practical usage
It feels like 'more Opus' and can modernize 15,000-line codebases, though it requires back-and-forth debugging for complex tasks.
Cost and limits
The model is expensive at $10/$50 per million tokens and has strict 5-hour session limits, burning $100 in just 8 minutes.
Safety trade-offs
While Cloud Code is mostly permissive, the model uses 'steering vectors' to dumb down responses for sensitive topics like cybersecurity without notifying the user.
Usage strategy
You should use it to solve problems five times harder than usual, letting it run autonomous workflows like writing fuzzers or refactoring stale PRs.
Use this with an agent
Copy or download either the structured summary or the full transcript.
Have your own business or tech recording?
Turn demos, webinars, strategy calls, and tech talks into transcripts, summaries, and agent-ready briefs.
Keep exploring
More summaries from the Typist library — picked for the same category
0 to $300k/mo in 45 days with my ai app (just copy me)
Superwall
Nouriel Roubini on Iran War, Oil Shock, AI Boom
Bloomberg Television
Did Claude really get dumber again?
Theo - t3․gg
How This Solo AI Founder Bootstrapped 5 Products to 1M+ / Month | Tibo Louis-Lucas
Peter Yang