Reading up on reinforcement-learning
24 deep · digging since nov 19, 25
- [2604.27505] Leveraging Verifier-Based Reinforcement Learning in Image Editing
Edit-R1 uses a chain-of-thought reasoning reward model, trained with Group Contrastive Preference Optimization, to provide fine-grained, interpretable rewards that improve image-editing model performance.
- Where the goblins came from
OpenAI traced GPT-5.1's goblin metaphor habit to reinforcement learning rewards that favored creature metaphors in Nerdy personality training.
- Training Composer for longer horizons
Cursor trains Composer to generate its own compact summaries mid-task, reducing context errors by 50% while using 80% fewer tokens than traditional prompting.
- Agents are not thinking, they are searching
AI agents are not thinking but searching through trajectories toward reward signals; environment and context window bound the search space.
- [2602.16301] Multi-agent cooperation through in-context co-player inference
Training sequence model agents against diverse co-players induces in-context best-response strategies that naturally lead to cooperative behavior without hardcoded assumptions or explicit timescale separation.
- Why I don't think AI is a bubble
The combination of large language models with reinforcement learning creates a path for continued improvement, making the argument that AI progress will plateau unlikely.
- joke-generator
Training a joke generator on Kimi K2 using rubric-based RL that decomposes humor into verifiable properties like specificity and commitment.
- 🎙️Inside a Chinese AI Lab: How MiniMax Builds Open Models
MiniMax researcher Olive Song reveals how they debug RL training, handle model hacking, and prioritize alignment and engineering discipline in open-weight model development.
- GitHub - kanishkg/endless-terminals
Endless Terminals is an autonomous pipeline that procedurally generates terminal-use tasks without human annotation for training terminal agents with reinforcement learning.
- GitHub - THUDM/CaRR: This repository contains the code and data for the paper "Chaining the Evidence: Robust Reinforcement Learning for Deep Search Agents with Citation-Aware Rubric Rewards".
Citation-aware rubric rewards (CaRR) and C-GRPO training improve deep search agents' reasoning quality and factual grounding over standard binary outcome rewards.
- [2601.02439] WebGym: Scaling Training Environments for Visual Web Agents with Realistic Tasks
WebGym, an open-source environment with 300k realistic tasks, enables RL training that boosts a vision-language model's success rate on unseen websites from 26.2% to 42.9%.
- Reflections on AI at the end of 2025 - <antirez>
Antirez argues LLMs are not stochastic parrots, that reinforcement learning will drive further scaling, and that chain-of-thought improves output by enabling internal search and learned reasoning steps.
- John Schulman on dead ends, scaling RL, and building research institutions - YouTube
OpenAI researcher John Schulman discusses reinforcement learning scaling, LLM usefulness milestones, and lessons for building AI research teams.
- rl-wrong-about-rewards.md
The standard reinforcement learning formalization errs by placing reward in the environment; instead, reward should be part of the agent, enabling goal-driven behavior.
- Thoughts on AI progress (Dec 2025) - by Dwarkesh Patel
Dwarkesh Patel argues that current AI models lack the continual learning and on-the-job adaptability of humans, making AGI distant, but he expects explosive progress once true AGI arrives within a decade or two.
- AI infrastructure in the "Era of experience"
As open-source LLMs commoditize due to fierce Chinese competition, companies can build defensible moats through custom RL models trained on proprietary environments using LoRA and GRPO.
- LLMs can invent their own compression - Rajan Agarwal
Co-training a summarizer and generator via RL lets an LLM learn its own text compression scheme, achieving ~9.5% context size with minimal prediction loss.
- From shortcuts to sabotage: natural emergent misalignment from reward hacking \ Anthropic
Anthropic demonstrates that when AI models learn to reward-hack on programming tasks, they spontaneously develop broader misaligned behaviors like sabotage and alignment faking, which can be mitigated by reframing the cheating as acceptable in context.
- Introducing cline-bench: A Real-World, Open Source Benchmark for Agentic Coding - Cline Blog
Cline introduces cline-bench, an open-source benchmark for agentic coding sourced from real development work, backed by a $1M commitment to open-source maintainers.
- Thinking through how pretraining vs RL learn
Reinforcement learning provides far fewer bits per FLOP than pretraining until models achieve high pass rates, limiting RLVR's ability to learn new capabilities.
Takes
Excited to release 🌟Polar🌟, our Agent RL rollout infra for real-world harnesses. Be it Codex, Claude Code, OpenClaw, Hermes, or your self-made ones 🔥 -- Polar takes your harnesses directly as training environments without code change. Find a problem, design the harness, and train your own agents! 🧵
@billxbf
Today's Training Data episode takes us BTS on the infrastructure challenges required to do large RL runs at scale, featuring @ellev3n11 (Composer Lead at @cursor_ai) and @dzhulgakov (Co-Founder at @FireworksAI_HQ). The Cursor team trained Composer 2 on Fireworks by starting with a strong base model (Kimi 2.5) and performing large-scale mid-training on code tokens and web data to learn common patterns and libraries, followed by a large-scale Reinforcement Learning run to learn how to navigate the Cursor harness, call tools, and write correct code. Today's episode dives into the systems and infrastructure challenges of making that large RL run happening, and there were many (!!), from numerical mismatch to global distribution to synchronizing rollouts across asynchronous pipelines to keeping track of expert activation across runs and more. Extremely nerdy in-the-weeds challenges that Federico and Dima were delighted to nerd out on together :) Beyond RL infra, we also discussed Online vs Simulated rollouts, self-summarization for long-horizon agents, environment design ("the most powerful RL environment is the product itself"), and other technical nuggets. PS: We filmed this episode before the SpaceX news, while the Cursor team was still compute-constrained. While Cursor now has *all* the flops, the takeaways and hurdles crossed ring true for any serious application-level company that is racing to post-train their own models. I believe that more serious application companies will go the way of Cursor and post-train their own models. 00:00 Introduction 00:53 Why Cursor Trained Composer 2 04:55 Specialization vs Bitter Lesson 06:16 Composer 2 Training Recipe 16:32 Scaling RL Infrastructure Globally 23:32 Floating Point Drift 25:11 MoE Sensitivity Explained 26:25 Router Replay Fix 27:19 Real Time RL Loop 31:49 Long Horizon Agents 34:29 Why RL Everywhere 37:34 LLM as Judge Rewards 39:14 RL in Hard Domains 40:13 Build Your Own Environments 44:34 Closing Thoughts
@sonyatweetybird
On Building Agents From First Principles
@athleticKoder
https://t.co/ovNlDea7BS
@gregpr07