AI Agent Reliability Engineering in 2026: SLOs, Error Budgets, And Failure Modes That Actually Matter 5/2/2026 Treating an AI agent like a normal service is how you get a 95 percent uptime number that hides a 60 percent task success rate. The teams running real agent products in 2026 measure reliability differently, set SLOs on outcomes instead of HTTP codes, and have rehearsed every failure mode the agent introduces. Here is what that looks like.