diff --git a/.planning/phases/04-notifications-et-i3bar/04-02-PLAN.md b/.planning/phases/04-notifications-et-i3bar/04-02-PLAN.md
index 9925195..1022f24 100644
--- a/.planning/phases/04-notifications-et-i3bar/04-02-PLAN.md
+++ b/.planning/phases/04-notifications-et-i3bar/04-02-PLAN.md
@@ -2,8 +2,8 @@
 phase: 04-notifications-et-i3bar
 plan: 02
 type: execute
-wave: 1
-depends_on: []
+wave: 2
+depends_on: ["04-01"]
 files_modified: [i3bar.go, i3bar_test.go, main.go]
 autonomous: false
 requirements: [I3-03]
diff --git a/.planning/phases/04-notifications-et-i3bar/04-VALIDATION.md b/.planning/phases/04-notifications-et-i3bar/04-VALIDATION.md
new file mode 100644
index 0000000..2db771b
--- /dev/null
+++ b/.planning/phases/04-notifications-et-i3bar/04-VALIDATION.md
@@ -0,0 +1,75 @@
+---
+phase: 4
+slug: notifications-et-i3bar
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-03-24
+---
+
+# Phase 4 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | go test (stdlib) |
+| **Config file** | go.mod (exists) |
+| **Quick run command** | `go test ./...` |
+| **Full suite command** | `go test -v -race ./...` |
+| **Estimated runtime** | ~6 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `go test ./...`
+- **After every plan wave:** Run `go test -v -race ./...`
+- **Before `/gsd:verify-work`:** Full suite must be green
+- **Max feedback latency:** 6 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| 04-01-01 | 01 | 1 | NOTIF-01, NOTIF-02 | unit | `go test -run 'TestNotify\|TestFocus' ./...` | ❌ W0 | ⬜ pending |
+| 04-01-02 | 01 | 1 | NOTIF-01, NOTIF-02 | unit | `go test -run 'TestDaemonNotify\|TestDaemonFocus' ./...` | ❌ W0 | ⬜ pending |
+| 04-02-01 | 02 | 2 | I3-03 | unit | `go test -run 'TestFormatI3Bar' ./...` | ❌ W0 | ⬜ pending |
+| 04-02-02 | 02 | 2 | I3-03 | build | `go build -o /dev/null ./...` | ✅ | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+- [ ] Test stubs for notify, focus, i3bar formatting
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| Dunst notification appears on Working→NeedsInput | NOTIF-01 | Requires real dunst + Claude session | Trigger tool_use permission, verify notification popup |
+| Focus timer suppresses notifications | NOTIF-02 | Requires real notification stack | Run `vmux focus 1`, trigger transition, verify no popup |
+| i3bar widget displays in i3 status bar | I3-03 | Requires real i3 config | Configure i3 status_command, verify widget appears |
+
+---
+
+## 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 < 6s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending