deep-dive

<Purpose> Deep Dive orchestrates a 2-stage pipeline that first investigates WHY something happened (trace) then precisely defines WHAT to do about it (deep-interview). The trace stage runs 3 parallel causal investigation lanes, and its findings feed into the interview stage via a 3-point injection mechanism — enriching the starting point, providing system context, and seeding initial questions. The result is a crystal-clear spec grounded in evidence, not assumptions. </Purpose> <Use_When> - User has a problem but doesn't know the root cause — needs investigation before requirements - User says "deep dive", "deep-dive", "investigate deeply", "trace and interview" - User wants to understand existing system behavior before defining changes - Bug investigation: "Something broke and I need to figure out why, then plan the fix" - Feature exploration: "I want to improve X but first need to understand how it currently works" - The problem is ambiguous, causal, and evidence-heavy — jumping to code would waste cycles </Use_When> <Do_Not_Use_When> - User already knows the root cause and just needs requirements gathering — use `/deep-interview` directly - User has a clear, specific request with file paths and function names — execute directly - User wants to trace/investigate but NOT define requirements afterward — use `/trace` directly - User already has a PRD or spec — use `/ralph` or `/autopilot` with that plan - User says "just do it" or "skip the investigation" — respect their int...