OpenAI's Astra beats Fable 5.1 19-to-8 on robot arms

OpenAI ran its Astra model on real bimanual robot arms and won big on one task, badly on another. In results published September 4, RoboCurve tested Astra and Fable 5.1 head to head, 20 trials each, on I2RT YAM arms through the Inspect Robots 0.58.0 harness.

On the coarse task, putting a block into a bowl, Astra hit 19 of 20 tries. Fable 5.1 managed 8, and an older Fable 5 managed 1. Astra also did it cheaper and faster: $0.94 a run against Fable 5.1's $2.12, 2.5 minutes against 6.8, and 2,100 output tokens against 12,900.

The second task tells a different story. Fitting a puzzle piece into a groove asks for tighter precision, and both models scored exactly 2 of 20 attempts. Whatever let Astra beat Fable 5.1 on block-into-bowl didn't carry over. The benchmark doesn't say why the gap closes on the harder task, only that it does.

That split matters more than the headline number. A model that's 19/20 on coarse placement and 2/20 on tight-tolerance work isn't ready to run a warehouse pick line or assemble anything with fitted parts. It's ready for tasks that look like dropping a block in a bowl, which is a narrower claim than "OpenAI's robot model wins."

Watch whether the next round of testing adds a task between those two extremes. Right now there's a wide gap between "easy and Astra dominates" and "hard and both models are equally bad," and nothing here tests what's in between.