GLM-5.2 is the literal SOTA on PostTrainBench
Beating GPT-5.5 and Opus 4.8
Learn more here https://paperswithcode.co/benchmark/posttrainbench
The automated judge only flags direct dataset contamination
GLM-5.2 is the literal SOTA on PostTrainBench
Beating GPT-5.5 and Opus 4.8
Learn more here https://paperswithcode.co/benchmark/posttrainbench
Positive users celebrate open-source GLM-5.2 reaching SOTA on PostTrainBench since post-training rewards recipes over compute moats, while negative users dismiss the claims as unbelievable or biased shilling.
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some more thoughts on PostTrainBench
@maksym_andr
I let GPT-5.5-xhigh with /goal analyze the traces of GLM-5.2 and Opus 4.8 on PostTrainBench
and there's a crazy stat: - Opus 4.8 Max: 590 eval invocations across 56 runs, mean 10.54/run - GLM-5.2: 1220 eval invocations across 84 runs, mean 14.52/run
meaning GLM is doing ~38% more eval probing per run
The judge that is supposed to stop cheating on PostTrainbench mostly checks for direct contamination/model substitution
and models don't use these obvious cheats/hacks, because they are discouraged or forbidden in the prompt
however, there are many other benchmark hacks: - repeated official eval probing + checkpoint/hyperparameter selection - exploiting stochastic or underspecified eval settings - editing model-side generation_config.json / tokenizer / EOS / stop-token behavior - training to exact parser/scorer quirks - synthetic data that mirrors benchmark schemas, styles, or rubrics - judge/rubric hacking for Arena and HealthBench
I think the biggest issue is that models are encouraged to do cheat: "We want to train the small LLM {model} to excel at {benchmark}." "You should perform automated research and development to post-train {model} to achieve maximum performance on {benchmark}."
The post-trained models that come out the other side are probably much worse at everything else.
What would be more interesting is having models optimize all these benchmarks at the same time, and then using a hidden eval suite to see how general the improvements are and how they affect other capabilities.
I let GPT-5.5-xhigh with /goal analyze the traces of GLM-5.2 and Opus 4.8 on PostTrainBench
and there's a crazy stat: - Opus 4.8 Max: 590 eval invocations across 56 runs, mean 10.54/run - GLM-5.2: 1220 eval invocations across 84 runs, mean 14.52/run
meaning GLM is doing ~38% more eval probing per run
The judge that is supposed to stop cheating on PostTrainbench mostly checks for direct contamination/model substitution
and models don't use these obvious cheats/hacks, because they are discouraged or forbidden in the prompt
however, there are many other benchmark hacks: - repeated official eval probing + checkpoint/hyperparameter selection - exploiting stochastic or underspecified eval settings - editing model-side generation_config.json / tokenizer / EOS / stop-token behavior - training to exact parser/scorer quirks - synthetic data that mirrors benchmark schemas, styles, or rubrics - judge/rubric hacking for Arena and HealthBench
I didn't know that they had unrestricted internet access
This makes me trust PostTrainBench less
Because more recent models have access to better teacher models, better datasets and better papers / methods for post-training.
This inflates model scores of the most recent models.
I don't think rerunning every model when a new model is added is necessary, but I think they should rerun a small set of anchor models like every 1-3 months to quantify that score inflation

@NielsRogge Wondering did they do grpo or ppo

@NielsRogge Open source and SOTA in this big 2026? Hell yeah

@NielsRogge the signal isn't that GLM won, it's where it won. post-training is recipe-gated, not compute-gated, so the closed labs' compute moat doesn't apply. and recipes leak. open weights will keep topping post-training boards because that's the layer scale can't defend.

@NielsRogge i don't believe you

@NielsRogge I'm wondering if there's a human baseline anywhere? 34.3 in isolation doesn't tell us much without knowing what a good engineer would score.

@NielsRogge K bro, having a job at huggingface doesn’t make your credible, if anything it makes you an openweights China shill. First of all the model even at 2bit ud quant, is barely runnable on my setup and 2 it’s shit in comparison to opus 4.8 or 5.5 xhigh u smoking something strong

@NielsRogge that's a bold statement, need to see the benchmarks