Large language models can now translate a researcher's plain-English request into a trading strategy that runs and produces backtest results. But as a new arXiv paper points out, a run that completes successfully is not the same as one that is correct. The strategy may encode the wrong rule, silently peek at future data, or hide its logic in ways that make review difficult.

The paper introduces QuantHarness, a framework for governing this process. Rather than focusing on maximizing returns, QuantHarness emphasizes reliability before profitability: it aims to catch mismatches between the user's intent and the implemented strategy, and to make the strategy's behavior transparent enough for oversight.

The abstract is brief, so details on how QuantHarness enforces these checks are not fully specified in the source. Still, the core message is clear: as LLM agents take on more quantitative finance work, the bottleneck shifts from generating strategies to verifying that they do what they claim to do.