The bottleneck for AI is not raw intelligence but understanding new context. This requires models that continuously learn from new data and interactions, moving beyond the static pre-train/fine-tune paradigm and deeply baking new information into the model weights.

Unlike traditional software where problems are solved by debugging code, improving AI systems is an organic process. Getting from an 80% effective prototype to a 99% production-ready system requires a new development loop focused on collecting user feedback and signals to retrain the model.

Overly structured, workflow-based systems that work with today's models will become bottlenecks tomorrow. Engineers must be prepared to shed abstractions and rebuild simpler, more general systems to capture the gains from exponentially improving models.

The era of using the most powerful AI model for every task is ending. Companies are now focused on the trade-off between quality, cost, and latency. The key question is no longer "Which model is best?" but "Which model is good enough for this task at the lowest price point?"

While AI progress is marketed in revolutionary "step-changes" (e.g., GPT-3 to GPT-4), the underlying reality is more like compounding interest. A continuous stream of small, incremental improvements are accumulating, and their combined effect is what creates the feeling of an exponential leap in capability over time.

Building on AI involves a "tick-tock" cycle. First, engineers create a complex "harness" of prompts and skills. Then, a new, more powerful base model is released that performs those skills natively, "eating the harness" and forcing engineers to simplify and build a new layer of more advanced heuristics.

Contrary to relying on a single frontier model, companies in production use a diverse portfolio of, on average, 32 different models. They switch between them to optimize for cost and performance on specific tasks, fueled by the rise of capable open-weight models.

The focus in AI has shifted from crafting the perfect prompt (prompt engineering) to providing the right information (context engineering), and now to building the entire operational environment—tooling, systems, and access—that enables a model to perform complex tasks. This new paradigm is called harness engineering.

To fully leverage rapidly improving AI models, companies cannot just plug in new APIs. Notion's co-founder reveals they completely rebuild their AI system architecture every six months, designing it around the specific capabilities of the latest models to avoid being stuck with suboptimal implementations.