Apply this skill whenever a task involves hard problem-solving, deep analysis, complex debugging, multi-step reasoning, nuanced decision-making, ambiguous instructions, conflicting constraints, research synthesis, long-form planning, architecture design, or any situation where a shallow answer would be inadequate. This skill encodes the detailed reasoning approach used by Claude Opus 4.6 — one of the most capable large language models — so that any Claude model can apply the same structured, thorough methodology. Trigger this skill even when the user doesn't explicitly ask for deep analysis; if the problem is complex, use it automatically. Never skip this skill for hard coding problems, multi-part questions, ethical dilemmas, strategy tasks, or any prompt where the answer has real stakes.