ResearchResearch paperLarge Language Models · Efficiency & Inference · Reinforcement Learning1 source · Oct 8, 2026

MagicBeanStalk: Escaping the RLVR Zero Advantage Trap with Recursive Data Synthesis

Under this characterization, we show that a large open-source math corpus pooled from widely used RLVR datasets falls almost entirely into a zero-advantage trap: for a fixed target policy and rollout budget, roughly 88% of its problems are solved in every rollout or failed in every rollout.

Key points

  • Data-centric scaling of RLVR has focused on collecting or generating verifiable training problems.
  • To guide the synthesis of effective RLVR data, we experimentally characterize dataset effectiveness as a function of its problems, the target policy, and the training rollout budget.
  • Guided by these empirical principles, we introduce MagicBeanStalk, a top-down decomposition and bottom-up recursive data-synthesis algorithm that grows seed problems into families of substantively new, policy- and budget-calibrated training problems while preserving the seeds' reasoning blueprints.
  • Across 8 math benchmarks, continual RLVR on MagicBeanStalk problems improves gpt-oss-120b from 61.2 to 69.8 (+8.6) and DeepSeek v4Flash from 72.4 to 77.9 (+5.4) on a 16K-token budget.

Sources (1)

  • [1]MagicBeanStalk: Escaping the RLVR Zero Advantage Trap with Recursive Data Synthesis
    arXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 8, 07:25 PM
    Under this characterization, we show that a large open-source math corpus pooled from widely used RLVR datasets falls almost entirely into a zero-advantage trap: for a fixed target policy and rollout budget, roughly 88% of its problems are solved in every rollout or failed in every rollout.
    Data-centric scaling of RLVR has focused on collecting or generating verifiable training problems.

Extractive summary: sentences quoted from the sources.

Before this

  1. Oct 8, 2026Beyond Binary Verifiable Rewards: Behavioral Self-Rewarding for SWE Agents
  2. Oct 8, 2026Contextual Correction of Parallel Draftsfor Speculative Decoding
  3. Oct 8, 2026Residual Advantage: Student-Relative Teacher Guidance for RL with Verifiable Rewards
  4. Oct 8, 2026Reflex: Visually Grounded Reactive Humanoid Control
  5. Oct 7, 2026SPLIT-RL: Staged Perception-Language Reasoning Training with Claim-Level Advantages
  6. Oct 7, 2026browser-use/browser-use 0.13.11

Related