A bank tracks one quality score for its customer-letter assistant: the average of four scores (relevance, factual accuracy, consistency and fluency) from an Amazon Bedrock evaluation job that uses custom judge metrics, with a release floor of 0.80. Release 12 scored 0.84 and shipped. Complaints about wrong interest rates followed. Analysis shows factual accuracy fell from 0.88 to 0.71 while fluency rose. The team wants the framework to catch this kind of regression. What should the team change?
Choose one.
An assessment framework for FM output scores several independent dimensions (relevance, factual accuracy, consistency, fluency). They must be reported and gated separately because they trade off against each other.
Release 12 improved fluency and lost factual accuracy, and the average let one cancel the other. A gate with a floor on each dimension blocks any release in which a critical dimension regresses, whatever happens to the others. A higher or reweighted average still allows compensation, and a single holistic score removes the diagnostic detail altogether.
- See that one dimension fell while another rose.
- Recognise that an average lets dimensions offset each other.
- Gate each dimension on its own threshold.
- Report the dimensions side by side so the cause is visible.
Exam tip: Gate GenAI quality per dimension; an average lets fluency hide factual errors.
AIP-C01 GenAI Evaluation: Output Quality Metrics, Bedrock Evaluations, A/B and Canary Testing, Quality Gates — the lesson that teaches this.