Collinear Newsletter #9 – Notes on Frontier AI
Hi AI innovators,
Nov was a massive month for agents as they took centerstage across NeurIPS and AWS Re:Invent!
NeurIPS2025 had a clear vibe: the agent era is forcing RL to grow up. Not as a research novelty, but as production infrastructure for tool use, long horizon behavior, and reliability when the world gets messy in real life workflows.
NeurIPS 2025, the “RL is everywhere” moment
San Diego served! Sunny weather, packed hallways, and surprisingly serious taco opinions. Between sessions (and coffee lines), we met a ton of builders and kept hearing the same thing: RL is suddenly everywhere.
RL is the new scaling lever. The frontier has shifted from “can the model answer?” to “can the agent execute?” Multi step work, tool calls, retries, and shifting user intent are pushing teams toward RL to shape end to end behavior.
RL needs the right infrastructure to go interactive. Environment fleets, verifiers, orchestration, NPCs - everyone at NeurIPS had a novel approach!
Realism is the new benchmark. Less obsession with a single score, more focus on trajectory shaped evals: does it hold up on turn4, recover from tool noise, and stay safe when scenarios drift?
We also presented our NeurIPS paper, Through the Valley of Reasoning. The punchline is: when you distill reasoning into small models, performance can dip before it climbs, and early on the structure of the reasoning matters more than whether the trace is “correct.”
We also met a bunch of new friends and collaborators. If you were there, hit reply and tell us what your team is building. We love swapping notes.
Spider, post training without the chaos
We shipped Spider, a lightweight way to turn post training work into a repeatable recipe.
With Spider, you can use one recipe for both off policy and on policy. Generate clean distillation datasets, or flip into an online loop with teacher guidance and KL supervision, without rebuilding your pipeline each time. It also keeps the “boring but critical” pieces consistent across runs, rollouts, filtering, verifiers, and publishing, so results stay comparable as you iterate.
Huge thanks to our friends at Thinking Machines for supporting the Tinker integration.
AWS Re:Invent - even more agents!
re:Invent turned Las Vegas into a full on agent showcase. Nova2 and the Nova family got a big spotlight, Nova Forge put “build your own frontier models” on the menu, and Nova Act made the case for agentic workflows!
What stood out to us was the framing in Swami Sivasubramanian’s agentic AI keynote: getting agents to production is less about clever prompts, and more about repeatable training and testing loops.
Congrats to our customers and partners at AWS on an awesome launch week.
If you are building agentic AI, we love to swap notes!
That’s it for this edition. Thanks for following along. We will have some fun things to share over the next couple of weeks. 🙂
Best,
The Collinear Team