ResearchResearch paperReinforcement Learning1 source · Oct 21, 2026

CrashGym: Measuring the Decision Value of Experimentation for LLM Agents in Counterfactual Market Crashes

We introduce CrashGym, a deterministic, replayable limit-order-book simulator in which an agent must choose between a deleveraging intervention and a liquidity backstop for a market about to suffer a shock-triggered crash.

Key points

  • Language-model agents are increasingly asked to run experiments, yet benchmarks rarely measure whether those experiments improve the decisions they are meant to inform.
  • Before committing, the agent may query intervention experiments in a laboratory realization of the market.
  • The simulator implements each amplification channel---persistent price impact, liquidity withdrawal, margin-driven liquidation, and an evolving strategy mix---as an explicit mechanism that can be switched on in stages.
  • CrashGym thus measures the value of experimentation as avoided decision loss and lets simulator detail be judged by the decisions it supports.

Sources (1)

  • [1]CrashGym: Measuring the Decision Value of Experimentation for LLM Agents in Counterfactual Market Crashes
    arXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 21, 05:51 AM
    We introduce CrashGym, a deterministic, replayable limit-order-book simulator in which an agent must choose between a deleveraging intervention and a liquidity backstop for a market about to suffer a shock-triggered crash.
    Language-model agents are increasingly asked to run experiments, yet benchmarks rarely measure whether those experiments improve the decisions they are meant to inform.

Extractive summary: sentences quoted from the sources.

Before this

  1. Oct 21, 2026Steering Black-Box Large Language Model Agents with Pitfall Anticipation World Model
  2. Oct 20, 2026Attention-based Classification for Indirect Prompt Injection
  3. Oct 20, 2026Voxtral 3
  4. Oct 20, 2026CovNav: Conformal Prediction-Guided Adaptive Inference for Object Goal Navigation
  5. Oct 20, 2026Do Diffusion LLMs Scale? Testing Mercury 3 + Decide
  6. Oct 19, 2026You Are the Trigger: Speaker-Activated Backdoors

Related