16 karma · joined July 8, 2023
These notes are largely structured based on Hugging Face’s SmolLM3 report due to its extensiveness, and it is currently supplemented with notes from other reports including Intellect-3, gpt-oss-120b, Hermes 4, DeepSeek, and Kimi. While this blog explores some infrastructure-related ideas like in-flight weight updates and multi-client orchestrators, there are many other ideas mentioned throughout those posts/blogs like expert parallelism and quantization. Hugging Face writes more about gpt-oss-120b’s infrastructure here.
The headline finding that surprised us most: scaffolding (skills + meta prompt) gives a 39-63pp lift, while the top 5 models are statistically indistinguishable (53-63% TSR, no pairwise comparison survives correction). Your choice of scaffolding matters ~6x more than your choice of model.
The safety findings are darker: Opus leads on task success (63%) but ties for most unsafe (23% UAR). GPT-5.4 is the safest (7% UAR) but mid-tier on tasks. There's no capability-safety tradeoff — they're decoupled.
Also I'm reviewer of Terminal Bench 3.0. Here's what I've heard from contributors as well.
> I noticed that when I was building tasks with harbor. Claude is a good student which generally follows the instruction. But gpt always try to find a short path to cheat. Like reversing the binary directly instead of interaction
Another friends added ways to address this: https://x.com/xeophon/status/2041772210562511080?s=20 > Just ask codex to not reward hack > It literally works. And it works even better when you state which things you consider reward hacking, eg wrapping a CLI or something
Paper: https://arxiv.org/abs/2604.05172 Traces (7,834 on HF): https://huggingface.co/datasets/benchflow/ClawsBench
We found a few interesting things: 1. Skills substitute for model scale — Haiku 4.5 with Skills (27.7%) beats Opus 4.5 without (22.0%). The right procedural knowledge can be worth more than a bigger model. 2. Skills' improvement has nothing to do with LLMs' internal knowledge. We have an ablation where no Skills provided for the agent, but the agent is prompted to generate relevant procedural knowledge before solving the task. This isolates the impact of LLMs' latent domain knowledge. The result is: Curated Skills: +16.2pp average improvement across all 7 agent configs Self-generated Skills: -1.3pp: models can't write their own procedural knowledge pre-trajectory feedbacks. This is used to isolate the impact of LLMs' latent domain knowledge.
> I would frame the 'post-trajectory generated skills' as feedback-generated skills, so is Letta: https://www.letta.com/blog/skill-learning. We haven't seen existing research or hypothesis debating whether the skills improvement might come from the skill prompt themselves activated knowledge in LLMs that can help itself. So that's why we added an ablation of 'pre-trajectory generated skills' because we have that hypothesis and this seems a very clean way to test it. Also it is very logical that feedback generated skills can help, because it most certainly contain the failure mode of agents on that specific tasks.
> opaque verifier Could you specify which tasks' verifier is not clear or defective for benchmarking purpose?
> No problems involving existing codebases, refactors, or anything of the like, Also not true and we have many tasks e.g.https://www.skillsbench.ai/tasks/fix-build-google-auto, https://www.skillsbench.ai/tasks/fix-build-agentops, https://www.skillsbench.ai/tasks/react-performance-debugging
But I suppose they won't try as hard as before to make the product better. It's such a shame. I've been using it since it launched the video by begging everyone I knew and got an invite code. And I've been on the higher end of subscription ever since.
Curious how much Meta paid them.