Confidence Check

Pre-implementation validation framework. Never code at < 90% confidence.

Why This Matters

Wrong-direction work costs 5K-50K tokens to undo. A 2-minute confidence check saves hours of rework.

The 90% Rule

Before implementing ANY significant change:

Confidence < 70%  → STOP. Research more.
Confidence 70-89% → PAUSE. Fill gaps first.
Confidence ≥ 90%  → PROCEED with implementation.

Confidence Checklist

1. Duplicate Check (20 points)

• Searched codebase for existing solution
• Checked if similar pattern exists elsewhere
• Verified not reinventing existing functionality

2. Architecture Alignment (20 points)

• Understand where this fits in the system
• Know which files/modules are affected
• Approach matches existing patterns

3. Requirements Clarity (20 points)

• Clear on what success looks like
• Understand edge cases
• Know acceptance criteria

4. Root Cause Understanding (20 points)

• If fixing bug: know WHY it happens
• If adding feature: know WHY it's needed
• Understand the problem, not just symptoms

5. Implementation Path (20 points)

• Know the steps to implement
• Identified potential blockers
• Have fallback approach

Scoring

Score each category 0-20:
- 0-5:   No understanding
- 6-10:  Partial understanding
- 11-15: Good understanding, some gaps
- 16-20: Full understanding

Total = sum of all categories (0-100)

Output Template

## Confidence Check: [Task]

### Assessment

| Category | Score | Notes |
|----------|-------|-------|
| Duplicate Check | /20 | |
| Architecture | /20 | |
| Requirements | /20 | |
| Root Cause | /20 | |
| Implementation | /20 | |
| **TOTAL** | **/100** | |

### Gaps Identified
- [ ] [gap 1 - how to fill]
- [ ] [gap 2 - how to fill]

### Verdict
**[PROCEED / RESEARCH MORE / STOP]**

### If RESEARCH MORE:
1. [specific question to answer]
2. [file to read]
3. [person to ask]

Quick Check (30 seconds)

For small changes, ask yourself:

1. Have I read the code I'm changing? (Y/N)
2. Do I know why this change is needed? (Y/N)
3. Do I know how to test it works? (Y/N)

All Y → Proceed
Any N → Pause and fill the gap

When to Skip

• Typo fixes
• Comment updates
• Obvious one-liners
• Explicitly requested by user with full context

Anti-Patterns

❌ "I'll figure it out as I go"
❌ "This looks similar to something I did before"
❌ "The user asked for it so it must be right"
❌ "I'll just try this and see"

✅ "I understand the problem and solution"
✅ "I've verified no existing solution"
✅ "I know exactly what files to change"