The Retrieval Layer Is Where Agency AI Margins Get Made or Lost

Clients now judge AI deliverables on whether outputs cite real sources, and retrieval quality decides that verdict long before prompt wording does. Agencies that treat RAG tooling as a swappable commodity behind their own evaluation harness can re-benchmark providers as accuracy shifts, while those that hard-wire one vendor inherit its pricing and its failure modes. The margin lives in the abstraction layer, not the API.