Executable solvers and world models
ReaComp gives the clearest efficiency result. It turns about 100 LLM reasoning traces per benchmark into reusable Python symbolic solvers. On PBEBench-Hard, the symbolic ensemble reaches 84.7% accuracy with no test-time LLM tokens, while Best-of-K reaches 68.4%. The hybrid also cuts reported token use by 78%.
The ARC-AGI-3 work applies the same discipline to interactive games. The coding agent writes a Python world model, checks it against observed transitions, plans inside it, and executes actions only while predictions keep matching. On 25 public games it fully solves 7, with large run-to-run variance and no private-set result yet.
UVMarvel extends the pattern to hardware verification. It builds Universal Verification Methodology (UVM) testbenches for subsystem-level RTL, then uses coverage reports and signal tracing to ask LLMs for new sequences. The paper reports 95.65% average code coverage across six subsystem benchmarks.