The hardest part of building an AI agent isn't writing the first version. It's the second week, when you're debugging why the agent loops, why tool calls fail silently, or why retrieval degrades after a few hundred sessions. That's the moment when framework choice stops being theoretical.
The past two years have produced a proliferation of agent frameworks, orchestration platforms, and infrastructure layers, each making a slightly different bet on how production agent systems get built. Some prioritize Python composability. Some bet on visual workflows. A few are solving the harder problem: how do you run an agent reliably when the connected tools, the underlying model, and the user intent are all moving targets simultaneously?
