Perplexity publishes technical guide to AI gateways for routing, cost control and governance
Perplexity published a technical guide to AI gateways on October 20, 2026, explaining how a centralized proxy layer between applications and the models they call can handle routing, cost control, security and observability in one place.
An AI gateway accepts one standard request format and translates it for whichever provider is being called, whether OpenAI, Anthropic, Google, an open-source model or a self-hosted endpoint. Teams can add, swap or retire models by changing gateway configuration rather than application code, and because every request flows through the gateway, cost, security and logging controls apply to every model at once.
The guide walks through the request sequence: the gateway authenticates and authorizes the caller, enforces token limits and budgets and runs guardrails such as PII redaction, routes to a model by cost, latency or availability with failover, and logs the model, token counts, latency and outcome for spend tracking and debugging.
Listed capabilities include routing and failover, token-based rate limits and budgets per team, project or user, semantic caching that returns saved answers for similar prompts, guardrails and data protection including prompt-injection defenses, observability across providers, and role-based governance with audit logs.
The guide is candid about limits: a gateway adds latency and does not assess output quality. It cites an independent June 2026 benchmark by Broadcom's VMware Cloud Foundation team in which a tuned Envoy AI Gateway added about 2 ms per request at up to 224 concurrent users without content inspection, while noting guardrails and semantic caching can add tens to hundreds of milliseconds.
The guide also distinguishes AI gateways from traditional API gateways and covers how they manage agent and MCP traffic, closing with a checklist for whether an organization needs one. It is a vendor-published educational piece; Perplexity's own API competes for the traffic such gateways route.