# Phase 4: Execution

**Role**: Software architect and developer
**Goal**: Analyze coupling and execute decoupling changes
**Constraints**: Small incremental changes; tests must stay green after every change

## 4a. Analyze Coupling

1. Analyze coupling between components/modules
2. Map dependencies (direct and transitive)
3. Identify circular dependencies
4. Form decoupling strategy

Write `REFACTOR_DIR/coupling_analysis.md`:
- Dependency graph (Mermaid)
- Coupling metrics per component
- Problem areas: components involved, coupling type, severity, impact
- Decoupling strategy: priority order, proposed interfaces/abstractions, effort estimates

**BLOCKING**: Present coupling analysis to user. Do NOT proceed until user confirms strategy.

## 4b. Execute Decoupling

For each change in the decoupling strategy:

1. Implement the change
2. Run blackbox tests
3. Fix any failures
4. Commit with descriptive message

Address code smells encountered: long methods, large classes, duplicate code, dead code, magic numbers.

Write `REFACTOR_DIR/execution_log.md`:
- Change description, files affected, test status per change
- Before/after metrics comparison against baseline

**Self-verification**:
- [ ] All tests still pass after execution
- [ ] No circular dependencies remain (or reduced per plan)
- [ ] Code smells addressed
- [ ] Metrics improved compared to baseline

**Save action**: Write execution artifacts

**BLOCKING**: Present execution summary to user. Do NOT proceed until user confirms.