Reproducibility

In late 2025, agentic coding tools went from impressive demos to daily infrastructure. The problem nobody talked about enough: when an LLM agent has write access to a codebase and no formal constraints, reproducibility breaks down. The Ralph Loop is a deterministic, story-driven execution framework that addresses this — one tool call per story, scoped writes, atomic state. A design rationale with a formal sketch of why the constraints matter.

On July 22, 2023, a Korean preprint claimed that LK-99 — a copper-doped lead apatite — was a room-temperature, ambient-pressure superconductor. Within six weeks, the claim was definitively falsified. The episode is more interesting for what it revealed about the sociology of science than for the compound itself: how a global community self-corrected at extraordinary speed, and how the media managed to fail at conveying uncertainty despite watching it happen in real time.