GPT-6-Astra: OpenAI's Fable-level Rottweiler. In my review of GPT-5.6 vs Fable, I called GPT-5.6-Sol a rottwiler vs Fable a wise owl. Sol was persistent, but intelligence was behind. With GPT-6-Astra, the intelligence level has gone up significantly, while persistence has been refined - it is less 'dumb persistent', but more 'look for creative solutions persistent.' There was a bunch of tasks, where previous models sort of worked, but ultimately didn't end up with anything useful. Now with GPT-6-Astra, they just clicked - de-slopified and finally made sense. Capabilities: - Game development or 3D is basically is at incredible level. Maybe not quite AAA, but it is a massive jump - Code optimisation - I had a bad vibe coded app and it cut my awful SQL code from 33k to about 1.8k without any loss of quality - Code migration - with 5.5 it basically didn't work, with 5.6-sol, it worked but with a lot of debugging, with 6-astra, I basically didn't bother to check - it was all perfect. This is a big deal. - Code Efficiency - I have been attempting to optimise FFmpeg - I got an average of 30% speed improvement, with some processes 2-3x faster. I am less sure of how this generalises, but shows promise. - Competence - it has fundamental competence about simple-ish things like setting up my camera, fixing chrome, clearing disk - that previous models were mediocre at - Computer use - just brilliant, feels solved - Front end - the UI capabilities are a LOT better, but I wouldn't say they are frontier, Fable is better. Some annoying tendencies still exist (brackets, blocks of text), but at least it is usable and if you ask to match to an existing design scheme - it is brilliant. Reasoning levels: - This is a change - before OAI models were quite bad at lower reasoning, I just never went below High - Right now, even Low feels pretty strong - I still wouldn't say that higher reasoning aren't better, but if it gets pricy, definitely consider whether lower reasoning is enough, it doesn't suck anymore Creativity: - Problem solving - there's something about Astra that just approaches things in a more insightful way, Sol would feel rigid and unable to get past an obsticle. - For example, it built me a little 'Air Hockey' game that you could play on a desktop, with each element being a shortcut, and it would interact with other files on my desktop. This requires re-imagining how different elements work and how one could be used in a different way. This is a refreshing change. Interaction: - Language - it is a model that feels very natural, I basically don't notice how it talks, which wasn't the case for Sol or many other models. It is clean, concise and understandable, I wasn't annoyed by anything - 'Swear index' - I have a local 'benchmark' which counts how often I swear at an agent. It got to basically zero with GPT-6, it stopped doing dumb stuff almost completely - In Codex it is very good at managing sub-agents, asking you questions (in a pop-up), it leaves notes for itself and for you about the findings - the whole experience is really quite pleasant Hard stuff: - I have tried maths problems - some worked (and were brilliant), but a lot didn't. So when you see the maths breakthroughs, know that it is still not a matter of just asking any question and getting an answer. It is mostly about fining the right problem it can actually solve. - The quality of writing maths papers is still quite poor. It still doesn't seem to really understand what is interesting or important and mostly dumbs a lot of maths in the write ups. We need a paper writing skill urgently - If you don't know an area it can still be unhelpful - if you can't point the model in the right direction, it would probably struggle. Like with other models, it is best that you have the foresight and knowledge of what you are ultimately doing So is it better than Fable? It is close. Fable is an incredible model that can do a lot of the stuff that I described here and 5.1 especially smashes it on a lot of tasks. They are models of equivalent capability, but different 'shapes', so it depends more on the 'shape' of the model that you prefer. Price of GPT-6-Astra is 2.5x that of Sol and now matches Fable. This is a lot. So the key thing I want to look out for is token efficiency vs Fable. It feels more efficient, but I haven't done enough side by side to know for sure. We have a nice 'average cost per real task' view on the Agent Mode and I want to see how that comes out and where on the pareto they sit. It's a good model, and I am so happy that we have multiple models on the very top end of the capability. I hope we'll get more up there soon, from so many great labs.