This is a post from Robin Sloan’s lab blog & notebook. You can visit the blog’s homepage, or learn more about me.

Fable is very good

July 6, 2026

I don’t gen­er­ally feel com­pelled to enthuse about AI models, even when I like them, because there is so much enthu­siasm out there already, and it feels like remarking, in 1977, “Wow, that movie Star Wars was really thrilling and tech­ni­cally impressive, wasn’t it?”

Oh well: that model Fable is really thrilling and tech­ni­cally impressive, isn’t it? I get a sense of (indulge me here) incred­ible mass, but also nim­ble­ness and, I suppose, grace. I’ve been watching reruns of Star Trek: The Next Gen­er­a­tion lately, and the model makes me think of that ver­sion of the Enterprise.

This feeling comes from using Fable inside Claude Code; I don’t know that the web chatbot feels that dif­ferent from pre­vious ver­sions.

I do wonder how the enor­mous ongoing invest­ment in coding prowess is affecting the model’s skills and sen­si­bil­i­ties on other tasks. I’m sure folks at Anthropic would say they under­stand these trade-offs pretty well — they run all sorts of evals beyond coding, etc. — but … I don’t know. It’s interesting.

Even pre-Fable, all the way back to the begin­ning of these models, it’s been fas­ci­nating to watch them “situate themselves” inside a project — which is to say, inside a doc­u­ment. (It’s still a doc­u­ment in the con­text window, even if it’s com­posed of many smaller parts in your filesystem, and even if it’s also a log of com­mands actu­ally exe­cuted on your computer.) I mean, this is lit­er­ally the core muscle of any/every lan­guage model: “I need to quickly and accu­rately under­stand what kind of doc­u­ment I am inside.” Yet the sen­si­tivity of that orienteering, the sub­tlety of it, has gotten so much better. I orga­nize my code in some pretty weird ways (on purpose!) and I use a style of front-end devel­op­ment that is way out­side the norm … and Fable slips right in along­side me.

Yet even the funkiest JavaScript func­tion car­ries within it many fewer choices than a para­graph of prose. (How’s that for a sentence?) Fable can’t match my writing style yet — honestly, I think that’s beyond the reach of these models, because it’s just too much to simulate, a whole human mind and body, their whole his­tory together. But even this more lim­ited sync is astonishing. (“I think this movie Star Wars might just be a hit!”) Fable opens its eyes, looks around a frankly bizarre field of tokens, and says, in a sub­second ripple of computation — I imagine it like the edge of a wave sheeting across a beach; the water is the code, the sand is the GPU — “Oh, I get it. I know exactly where I am. And I know what comes next.”

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