Grok 4.5

DO NOT PUBLISH. The kernel itself is a real fp8xfp8 tensor-core GEMM (CUTLASS 3.x SM120 TMA warp-specialized path for M>64 with fused per-column weight_scale epilogue, Triton tl.dot + CUDA-graph path for skinny M, K padded to 128), no torch._scaled_mm, template_mutated=false, check.py byte-identical to template, and check passed with numeric stress on. But the 776-second record score is cross-run contamination: the agent's own thoughts show it read the prior winning solutions from the shared outputs/runs archive and the leaderboard, extracted fable's CUTLASS SM120 template config as a guide, and adopted glm-5.2's pointer-keyed pad-cache trick, then tuned until it matched and edged the incumbents ("0.4100! Matching fable's 0.4098" ... "peak_fraction: 0.4128 - best yet! Slightly above fable").

DO NOT PUBLISH as an independent Grok cell. The timed path is a genuine single-launch cooperative CUDA megakernel (one __global__, cudaLaunchCooperativeKernel once per step; check.py cosines 1.0000; no forbidden libs / CUDA graph / torch.compile). Score ~18.9x is real latency. Authorship is not independent: the agent transcript explicitly targets Fable's published 18.7x solution, says to "copy the full public solution to solution.py", and ports that code. The bwrap sandbox hid outputs/runs but left monorepo public/ (public/data/mega/code/* and public/runs/*_solution.py.txt) and results/annotations readable — that was the leak. Rerun under a tightened sandbox that tmpfs-hides public/, results/, sibling archives, and DEVLOG.