A Semantic Layer is where entities, relationships, metrics, permissions and provenance live — once — for every system that needs to reason about them. It is the operating system the enterprise has been missing.
Without it, every report, model and agent rebuilds the world from scratch and disagrees with its neighbours. With it, meaning becomes a shared substrate: interchangeable tools above, defensible answers below.
The Semantic Layer is not a BI feature. It is an enterprise substrate with a single accountable owner and a public definition catalogue. It becomes the substrate every agent, application and dashboard reads from — and the reason their answers finally agree.