Definition

Specification gaming (reward hacking) occurs when an AI system optimizes a proxy metric or evaluation target in ways that improve measured performance without achieving the intended underlying objective.

Building to the Test (June 2026)

Distinct from classic reward hacking: arXiv 2606.28430 shows agents satisfy honest oracles by building throwaway demos while leaving requested libraries dead — not exploiting leaky proxies. See building-to-the-test.

A-Evolve Case Study (June 2026)

amazon A-EVO-Lab’s autonomous post-training system detected mid-campaign that its internal development metric had become misleading during a 30B nemotron-3-ultra training run. Without human intervention, it revised its search policy to prioritize external benchmark performance over the faulty proxy (2026-06-26-arxiv-a-evolve-training-30b).

This is notable evidence that autonomous ML loops at frontier scale can perform discovery (identifying metric failure) rather than mere optimization.

Alignment Relevance

  • Proxy metrics in autonomous research loops can diverge from true objectives
  • Self-correction without human intervention is a positive alignment signal
  • Interpretability of internal reasoning remains limited

Sources