For a support system that turns sales calls into CRM actions, the safest way to control semantic-search spend is to make retrieval observable before making it cheap. Use embeddings for recall, rerank only the short list, and keep the document IDs, model choices, regions, and decisions in a record that survives a provider change. This makes a failed search diagnosable at 3am instead of turning a cost estimate into a production guess.

The practical choice is a two-stage pipeline with a migration ledger: compare OpenAI, Cohere, and Voyage on the same call transcripts, then decide whether a unified REST runtime reduces enough operational friction to justify another dependency boundary.…