pre-implementation-review

Pre-Implementation Review

Purpose

The gap between "good plan" and "good implementation" is where most bugs are born. This gate ensures the plan survives adversarial scrutiny BEFORE any code is written.

Auto-Invocation Trigger

Invoke when transitioning from planning to implementation — specifically:

• After writing-plans skill produces an implementation plan
• Before executing-plans skill begins work
• Before any multi-file implementation begins
• When a design doc exists and coding is about to start

Checklist

You MUST create a TodoWrite task for each step:

1. Sentinel scan on the implementation plan — run sentinel with the plan description as content. This catches complexity risks the planning phase may have introduced.

2. Cross-exam the plan with all 3 surgeons — focus question: "What will break when we implement this?" Not "is this a good idea?" (that was architectural-gate's job) but "what will go wrong during execution?"

3. Counter-position: argue why this plan will FAIL — invoke the counter-position skill. The claim is "this implementation plan will succeed." Steelman why it will not.

4. Verify gains-gate passes — infrastructure must be healthy before starting. Do not build on broken foundations.

5. Create explicit rollback strategy — before writing code, document how to undo the changes if they go wrong. This forces thinking about reversibility.

6. Present review results — summarize findings from steps 1-5. Proceed only with approval. If surgeons raised critical concerns, those must be addressed in the plan before implementation begins.

What the Cross-Exam Should Focus On

The cross-exam question for pre-implementation is specifically:

We are about to implement the following plan:
[plan summary]

Focus your analysis on:
1. What will break during implementation?
2. What dependencies or ordering constraints are missing?
3. What edge cases does the plan not address?
4. Are there simpler approaches the plan overlooked?
5. What tests should exist BEFORE implementation starts?