This source appears to be a tutorial about constructing a basic AI agent from scratch. Based only on the title, its focus is likely long-task planning: how an agent breaks a larger objective into steps and works through them over time. No article body was provided, so specific implementation choices, model providers, tools, code examples, or evaluation results cannot be confirmed.
This GitHub project presents a formally verified multipolygon intersection algorithm checked in Lean 4. The author argues trust comes from the Lean checker and a small human-reviewed specification, not from trusting LLM output directly. It also documents how Claude Opus versions improved on Lean proof work, with Opus 4.8 reportedly completing larger proof strategies that earlier attempts could not.