Constraining the Coding Agent: The Ralph Loop and Why Determinism Matters
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.