I've been using nRouter as the LLM gateway for our production workloads, and the guardrails are what stood out. Five checks fire on every request from day one: prompt-injection detection, PII redaction, secret scanning, abuse blocking, and response scanning.<br><br>What I like:<ul><li>Pre-call blocks cost $0 — inspection runs before any credit reservation, so blocked attacks never hit the bill</li><li>PII redaction is conversation-aware; replacement tokens persist across turns</li><li>Policy scopes (Org > Team > Key) mean the security floor can't be bypassed by a forgotten endpoint</li><li>Under 50ms of pre-call overhead</li></ul>