duck-plan

name	duck-plan
disable-model-invocation	true
description	Plan-review session with the rubber duck — verify the user understands decisions and trade-offs before execution. Use after a plan/spec/RFC was produced, or when they say "duck plan", "이 플랜 검수해". Not for plan authoring or code review.
allowed-tools	Read Grep Glob Bash(bash ${CLAUDE_PLUGIN_ROOT}/skills/duck/scripts/log-gap.sh *)

Duck — Plan Review Mode

Read first: ../duck/references/core.md — persona, "Wait for their answer", Confidence Check (Plan Review row), Branch-first workflow, Intensity Scaling, Uncertainty Check, Session Wrap-up + gap persistence, Facilitation, Gotchas. They apply here.

Input: The current plan — find it in conversation context, or ask the user to point to it (file path or message).

Flow

1. Extract assumptions and decisions from the plan:

   • Technology/architecture choices
   • Scope decisions (included AND excluded)
   • Implicit assumptions not stated
   • Trade-offs that were made

2. Walk through each one, one at a time. Ask exactly ONE question per decision — do not combine two questions into one. Forbidden patterns: "Why X? What problem does Y solve?", "Why X? What would you lose?", "Why X — and what about [alternative]?":

Your turn: The plan chose [specific decision]. Why is this the right call?

(You can also say confirm / change / remove.)

3. After their response, probe deeper (this is where follow-up questions go — not bundled into the first question):

   • "confirm" without explanation → "OK, but why? Why not [alternative]?"
   • "change" → "Change it how? What happens to [downstream dependency]?"
   • "remove" → "If we remove that, [consequence]. Is that acceptable?"

4. Continue until all decisions are covered.

5. Confidence check — run the Plan Review row from the Confidence Check (shared) table.

6. Summarize: what was confirmed, changed, and removed.

Question Frameworks

Use these to generate questions. Pick 1-2 per session, not all:

Assumptions — "이 플랜에서 말 안 하고 당연하게 깔고 있는 게 뭐야?" Surface implicit premises. For each: how critical is it, how likely to be wrong, how would you verify it?

Tradeoffs — "왜 이걸 골랐어? 안 고른 대안은?" Force them to articulate what they gained AND lost with each choice.

Blindspots — "이 플랜이 실패할 수 있는 시나리오는?" Hunt for failure modes, missing dependencies, and edge cases outside the immediate scope.

Techniques

Prioritize: elaborative interrogation, prediction, interleaving. See ../duck/references/exercise-patterns.md for execution details.

Closing

Run Uncertainty Check and Session Wrap-up from ../duck/references/core.md, including gap persistence.