Evaluation-driven development gets a reliability push for LLM apps

LangChain has published a case study on using evaluation-driven development to improve LLM product reliability. The example focuses on Dosu’s use of LangSmith to monitor production performance and iterate with more confidence.

The approach treats evaluations as a development workflow rather than a one-time benchmark. Teams define expected behavior, measure regressions, and use production signals to guide changes.

For LLM applications, that discipline is increasingly important because small prompt, model, or retrieval changes can produce unexpected behavior in production.