In the race to create powerful AI systems, many developers are focusing exclusively on the latest models. But real progress depends on a more disciplined process: understanding why AI is failing and knowing how to fix it. This practice, known as fault analysis, is the cornerstone of building effective „agent“ AI - systems that autonomously perform multi-step tasks. Let's unlock the secrets of this important skill and explore how the rapid evolution of large-scale language models (LLMs) is changing the game.
Why bug analysis is not as difficult as it seems
Imagine you're creating an AI for „deep research“ that writes detailed reports on complex topics. It works in several steps: generating search queries, retrieving results from the web, selecting sources, and finally writing the report. If the resulting report is of poor quality, the error may be in any of these steps.
Fault analysis is simply the process of opening the „hood“ and examining each step - or „footprint“ - to see where AI falls short compared to what an experienced human can do. This „human-level performance“ (HLP) benchmark is your guide.
A common misconception is that it requires a huge formal effort from day one. The opposite is true. You can start by informally reviewing just one or two failed cases. Did the AI generate meaningless search terms? This immediately points to the first area that needs improvement. As your system matures, you can expand this to a rigorous data-driven process, but the most important thing is the initial insight.
Key insight: Start small. A quick informal review of a few setbacks can reveal the most critical bottlenecks, allowing you to focus your engineering efforts where it matters.

New freedom: rethinking workflow design
Traditionally, redesigning the incremental AI process has been a monumental task. But thanks to the meteoric pace at which LLMs are improving, developers now have a powerful new option at their disposal: Simplify workflow by letting smarter LLMs do more. This often means „removing scaffolding“ - removing intermediate steps that were once necessary to guide a less capable model.
For example:
- Earlier: One AI could have cleaned up the messy website by removing ads and navigation bars before the other AI used that text to write the message.
- Now: Modern, smarter LLM can often directly understand unordered HTML, allowing you to remove the cleanup step entirely. This not only streamlines the process, but also eliminates potential errors caused by this extra step.
This change is crucial. If your error analysis reveals that a sequence of steps is not working correctly, even though every single step looks fine, it may be a sign that the workflow is too rigid. The solution is not to fix one step, but to redesign the process so that the AI has more autonomy and flexibility.
The way forward
The combination of disciplined error analysis and a willingness to rethink workflows is an effective recipe for success. By systematically identifying your AI's shortcomings and using increasingly powerful LLMs to simplify its tasks, you can create agent systems that are not only more powerful, but also more efficient and elegant. Mastering this iterative process of evaluation and redesign is what sets advanced AI development teams apart from the rest. In the world of AI, knowing what needs to be fixed and having the courage to rework is the ultimate competitive advantage.
The Batch - DeepLearning.AI by Andrew Ng / gnews.cz - GH