The biggest gap between demo and production isn't the model or the framework. It's three boring things: deterministic fallbacks (what happens when the agent fails or hallucinates), observability (can you trace exactly why an agent took action X), and cost controls (token budgets per task, not per call). Most teams get burned by the same pattern: the demo works beautifully, then in production you realize you need to handle the 15% of cases where the agent confidently does the wrong thing. The teams shipping successfully treat agents like junior employees, not autonomous systems. Guardrails first, autonomy second.