DART — frame before you fix

Most expensive mistakes come from a wrong mental model of the system, not weak execution. You act, the effect shows up later (delay), and you've already moved on. This skill is a gate: spend a few minutes building the right model before you touch the system.

Run it at three moments: before debugging, before designing/architecting, before reviewing. Same lens, different emphasis.

The gate: DART

A diagnostic to figure out which kind of system you're in before you pick a move. Real problems don't come with labels.

• D — Deconstruct. Break the problem into subparts. What is the system actually made of? Are the parts stable or constantly shifting? Name the stocks (where state piles up) and flows (what fills/drains them).
• A — Analyze (the key step). What is the link between cause and effect? This single question classifies the system:
  • obvious -> Clear
  • hidden but discoverable by analysis -> Complicated
  • only knowable in hindsight, emergent, shifting -> Complex
  • broken / no link -> Chaotic
• R — Recognize. Seen this before? Exact pattern, or similar in any other system. Match within and across systems (archetypes, anti-patterns, past incidents).
• T — Test. Run the smallest test that could falsify your model before committing to a full response. (Exception: in a Chaotic system there's no time — stabilize first.)