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:
code
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
code
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
markdown
## 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:
- •Have I read the code I'm changing? (Y/N)
- •Do I know why this change is needed? (Y/N)
- •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"