Well-Architected Framework Relied On Knowing The Call Graph. But Agents Are Not As Predictable.

For over a decade, we religiously used the well architected framework (WAF) in design reviews. Objective assessment with clear guidance from WAF made our designs risk free (or risk managed) with ambiguities and gaps called out. With agentic AI, there is always a little extra ambiguity. The rhythm of WAF does not strictly match one particular assumption underneath agentic AI: that we can diagram the execution path before the request arrives. All new ambiguities generally stem from this one root. I’ve run design reviews for more than a decade now. Amazon retail first, then AWS, then my own startup, and now healthcare. The rhythm never varied much. Scrutinize the design against the WAF pillars, weigh it against the alternatives, name the gaps and the risks and the open questions, turn the trade-offs into decisions, then move and manage what’s left in the risks. Whether we follow AWS’s six pillars, Google’s, or Microsoft’s four, the content is close enough that the muscle memory transfers. We are answering one question in six different registers: is this system built well enough to trust? And every design I reviewed in those years shared a property so basic that stating it sounds silly. We could enforce the execution path in advance. A single user request might fan out across dozens of services (or a few hundred in retail), queues, and databases, but an engineer could still draw the expected sequence diagram, project TPS for every service, point out the failure modes (and single points of failure), and estimate how much system stress one request would generate. Our early ML workloads (or traditional ML) fit that mold too. Request comes in, features go into a model, inference comes out, and the surrounding application decides what happens next. The model was a component with a latency budget, not a decision-maker. What actually broke, or started to smell Let me be precise about what did not break, because this gets muddled and debated constantly. The wire protocols are f