How to Choose an AI Gateway in 2026: The Checklist Engineers Actually Need

AI gateways are having their API-gateway moment and the vendor landscape is noisy enough that a structured decision framework is genuinely useful. This piece covers the dimensions that matter — model routing, fallback chains, rate limiting, spend controls, and observability hooks — in a checklist format that maps onto a real procurement or build-vs-buy decision. It is not exhaustive and it does not benchmark specific vendors against each other, which limits its usefulness as a final-stage reference. What it does do is give an engineer a vocabulary for the conversation with their team or a vendor, which has value when the category is still defining its own terminology. The absence of concrete vendor comparisons is the main gap — the checklist tells you what to ask but not how the major options actually score. -> Best for: AI engineer or technical PM about to evaluate or switch an LLM routing layer