Fable 5 dropped ~20 hours ago. On paper the jump is wild — 10+ points over Opus 4.8 on SWE-Bench Pro, nearly 2x the price per token, and Anthropic is calling it the first publicly available Mythos-class model. It’s included in Pro/Max/Team plans until June 22, then it moves to usage credits. Here’s my honest problem: Opus 4.8 already handles basically everything I throw at it. My day-to-day work just isn’t hard enough to surface the difference. I switched to Fable, ran my usual stuff, and the outputs were… also good? I genuinely can’t tell if I’m looking at a 10-point benchmark gap or a rounding error, because my tasks aren’t the bottleneck — I am. So I’m asking the people whose work actually lives at the frontier: Have you hit a task where Fable clearly succeeded and Opus 4.8 clearly failed? Same prompt, both models. A refactor, a long agentic run, a nasty debugging session — anything where the difference was unambiguous. The fallback question. In “high-risk” areas Fable apparently blocks and silently routes you to Opus 4.8. Has anyone hit this in normal work? How would you even know which model answered? If you’ve got concrete examples — prompts, diffs, before/after — please post them. I suspect a lot of us are in the same boat: paying attention to the benchmarks but unable to feel the difference ourselves. Show us what this model actually does at the edge. submitted by /u/Capital-Door-2293
Originally posted by u/Capital-Door-2293 on r/ClaudeCode