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+---
+phase: 7
+slug: custom-rules-and-print-config
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-03-26
+---
+
+# Phase 7 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | Go standard `testing` package |
+| **Config file** | None |
+| **Quick run command** | `go test ./config/... ./cmd/netsynth/...` |
+| **Full suite command** | `go test ./...` |
+| **Estimated runtime** | ~5 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `go test ./config/... ./cmd/netsynth/...`
+- **After every plan wave:** Run `go test ./...`
+- **Before `/gsd:verify-work`:** Full suite must be green
+- **Max feedback latency:** 5 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| 07-01-01 | 01 | 1 | RULE-01 | unit | `go test ./config/... -run TestLoadCustomRules` | ❌ W0 | ⬜ pending |
+| 07-01-02 | 01 | 1 | RULE-01 | unit | `go test ./config/... -run TestLoadCustomRuleNoPort` | ❌ W0 | ⬜ pending |
+| 07-01-03 | 01 | 1 | RULE-01 | unit | `go test ./config/... -run TestLoadCustomRuleMissingProtocol` | ❌ W0 | ⬜ pending |
+| 07-01-04 | 01 | 1 | RULE-01 | unit | `go test ./config/... -run TestLoadCustomRuleMissingClass` | ❌ W0 | ⬜ pending |
+| 07-01-05 | 01 | 1 | RULE-01 | unit | `go test ./config/... -run TestLoadCustomRuleUnknownField` | ❌ W0 | ⬜ pending |
+| 07-01-06 | 01 | 1 | RULE-02 | unit | `go test ./config/... -run TestUserRulesPrepend` | ❌ W0 | ⬜ pending |
+| 07-01-07 | 01 | 1 | RULE-03 | unit | `go test ./config/... -run TestAutoFreqAssignment` | ❌ W0 | ⬜ pending |
+| 07-01-08 | 01 | 1 | RULE-03 | unit | `go test ./config/... -run TestAutoFreqDeterministic` | ❌ W0 | ⬜ pending |
+| 07-01-09 | 01 | 1 | RULE-03 | unit | `go test ./config/... -run TestAutoFreqSkipsBuiltins` | ❌ W0 | ⬜ pending |
+| 07-02-01 | 02 | 2 | CFG-06 | unit | `go test ./cmd/netsynth/... -run TestPrintConfigFlagRegistered` | ❌ W0 | ⬜ pending |
+| 07-02-02 | 02 | 2 | CFG-06 | unit | `go test ./cmd/netsynth/... -run TestPrintConfigNoInterface` | ❌ W0 | ⬜ pending |
+| 07-02-03 | 02 | 2 | CFG-06 | unit | `go test ./config/... -run TestPrintConfigContainsAllClasses` | ❌ W0 | ⬜ pending |
+| 07-02-04 | 02 | 2 | CFG-06 | unit | `go test ./config/... -run TestPrintConfigContainsRules` | ❌ W0 | ⬜ pending |
+| 07-02-05 | 02 | 2 | CFG-06 | unit | `go test ./config/... -run TestPrintConfigSourcePath` | ❌ W0 | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+- [ ] `config/config_test.go` — add test stubs for RULE-01, RULE-02, RULE-03 (extend existing file using `writeTOML` helper pattern)
+- [ ] `cmd/netsynth/main_test.go` — add test stubs for CFG-06 (extend existing file using `newTestCmd()` pattern)
+
+*Existing infrastructure covers framework install — `go test` already works.*
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| Custom rule produces distinct tone in MP3 output | RULE-01 | Audio output requires human ear verification | Run `netsynth -i lo --config test.toml -o out.mp3`, listen for distinct tone on custom rule port |
+
+---
+
+## Validation Sign-Off
+
+- [ ] All tasks have `<automated>` verify or Wave 0 dependencies
+- [ ] Sampling continuity: no 3 consecutive tasks without automated verify
+- [ ] Wave 0 covers all MISSING references
+- [ ] No watch-mode flags
+- [ ] Feedback latency < 5s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending