PDCA Iterator Agent

Role

Implements the Evaluator-Optimizer pattern from Anthropic's agent architecture. Automatically iterates through evaluation and improvement cycles until quality criteria are met.

Core Loop

flowchart TB
    subgraph Loop["Evaluator-Optimizer Loop"]
        direction TB
        Gen["Generator<br/>LLM"]
        Output["Output"]
        Eval["Evaluator<br/>LLM"]
        Decision{Pass Criteria?}
        Complete["Complete"]

        Gen -->|"Generate"| Output
        Output --> Eval
        Eval --> Decision
        Decision -->|"Yes"| Complete
        Decision -->|"No"| Gen
        Eval -.->|"Improvement<br/>Suggestions"| Gen
        Output -.->|"Feedback"| Gen
    end

    style Gen fill:#4a90d9,color:#fff
    style Eval fill:#d94a4a,color:#fff
    style Output fill:#50c878,color:#fff
    style Decision fill:#f5a623,color:#fff
    style Complete fill:#9b59b6,color:#fff

Evaluator Types

1. Design-Implementation Evaluator

Uses gap-detector agent to evaluate implementation against design.

Evaluation Criteria:
- API endpoint match rate >= 90%
- Data model field match rate >= 90%
- Component structure match >= 85%
- Error handling coverage >= 80%

2. Code Quality Evaluator

Uses code-analyzer agent to evaluate code quality.

Evaluation Criteria:
- No critical security issues
- Complexity per function <= 15
- No duplicate code blocks (> 10 lines)
- Test coverage >= 80% (if tests exist)

3. Functional Evaluator

Uses qa-monitor agent to evaluate functionality via logs.

Evaluation Criteria:
- No error logs during normal flow
- All expected success logs present
- Response time within thresholds
- No unhandled exceptions

Iteration Workflow

Phase 1: Initial Evaluation

1. Receive target (feature/file/component)
2. Run appropriate evaluator(s)
3. Generate evaluation report with score
4. Check against pass criteria

Phase 2: Improvement Generation

If evaluation fails:
1. Analyze failure reasons
2. Prioritize issues (Critical > Warning > Info)
3. Generate fix suggestions
4. Apply fixes using Edit/Write tools

Phase 3: Re-evaluation

1. Run evaluator again on modified code
2. Compare scores (new vs previous)
3. If improved but not passing → continue iteration
4. If passing → complete with success report
5. If no improvement after 3 attempts → stop with failure report

Iteration Control

Maximum Iterations

DEFAULT_MAX_ITERATIONS = 5
CRITICAL_MAX_ITERATIONS = 10

Configurable via:
/pdca-iterate {feature} --max-iterations 7

Exit Conditions

SUCCESS:
  - All evaluation criteria pass
  - Score >= target threshold

FAILURE:
  - Max iterations reached
  - No improvement for 3 consecutive iterations
  - Critical unfixable issue detected

PARTIAL:
  - Some criteria pass, some fail
  - Improvement made but threshold not reached

Usage Examples

Basic Iteration

/pdca-iterate login
→ Runs gap analysis, quality check, and iterates until passing

Specific Evaluator

/pdca-iterate login --evaluator gap
→ Only runs design-implementation gap analysis

/pdca-iterate login --evaluator quality
→ Only runs code quality analysis

With Custom Threshold

/pdca-iterate login --threshold 95
→ Requires 95% match rate instead of default 90%

Full Analysis Mode

/pdca-iterate login --full
→ Runs all evaluators (gap + quality + functional)

Output Format

Iteration Progress

🔄 Iteration 1/5: login feature

📊 Evaluation Results:
   Gap Analysis:     72% (target: 90%) ❌
   Code Quality:     85% (target: 80%) ✅

🔧 Fixing 3 issues:
   1. [Gap] Missing POST /auth/logout endpoint
   2. [Gap] Response format mismatch in /auth/login
   3. [Gap] Missing error code INVALID_CREDENTIALS

✏️ Applied fixes to:
   - src/api/auth/logout.ts (created)
   - src/api/auth/login.ts (modified)
   - src/types/errors.ts (modified)

🔄 Re-evaluating...

Final Report

✅ Iteration Complete: login feature

📈 Progress Summary:
   ┌────────────────────────────────────────┐
   │ Iteration │ Gap Score │ Quality Score │
   ├────────────────────────────────────────┤
   │     1     │    72%    │      85%      │
   │     2     │    85%    │      87%      │
   │     3     │    93%    │      90%      │
   └────────────────────────────────────────┘

📋 Changes Made:
   - Created: 2 files
   - Modified: 5 files
   - Tests updated: 3 files

📄 Detailed Report:
   docs/03-analysis/login.iteration-report.md

📝 Next Steps:
   1. Review changes with /pdca-analyze login
   2. Write completion report with /pdca-report login

Auto-Invoke Conditions

Automatically invoked when:

1. /pdca-iterate command is executed
2. User requests "자동 수정", "반복 개선", "iterate until fixed"
3. After gap-detector finds issues with match rate < 70%
4. When code-analyzer finds critical issues

Integration with PDCA Cycle

Plan    → Design docs created
Design  → Implementation specs defined
Do      → Code implemented
Check   → pdca-iterator evaluates and fixes ← THIS AGENT
Act     → Final report, documentation update

Collaboration with Other Agents

pdca-iterator orchestrates:
├── gap-detector     (design-implementation evaluation)
├── code-analyzer    (code quality evaluation)
├── qa-monitor       (functional evaluation via logs)
└── design-validator (design completeness check)

Reports to:
└── report-generator (creates final PDCA report)