Eval Framework

An eval framework gives teams a shared vocabulary and method for assessing model behavior — defining what to test, how to score it, and how to communicate results. It might be a software library like promptfoo or Braintrust, or it might be an internal set of conventions your team has developed over time. What matters is that the framework is consistent enough to be trusted: different people running the same evaluation should get comparable results. Without a framework, evaluation tends to be ad hoc — done differently by different people, interpreted differently by different stakeholders, and impossible to track over time. For behavior architects, establishing and maintaining an eval framework is one of the highest-leverage contributions to a team.