diff --git a/docs/design/development-plan-v2.6.md b/docs/design/development-plan-v2.6.md
index 7cc6e98..a9b875d 100644
--- a/docs/design/development-plan-v2.6.md
+++ b/docs/design/development-plan-v2.6.md
@@ -260,8 +260,8 @@ Layer 6: F17 SSE+Hook → F18 前端
 | F3 | 多项目管理 | ✅ 完成 | ✅ 11/11 | ✅ 通过 |
 | F4 | CLI 工具 | ✅ 完成 | ✅ 14/14 | ✅ 通过 |
 | F5 | API 层 | ✅ 完成 | ✅ 23/23 | ✅ 通过 |
-| F6 | Daemon Ticker | ✅ 完成 | ✅ 18/18 | ⬜ 待审 |
-| F7 | Inbox JSONL | ⬜ 待开始 | — | — |
+| F6 | Daemon Ticker | ✅ 完成 | ✅ 18/18 | ✅ 通过 |
+| F7 | Inbox JSONL | ✅ 完成 | ✅ 16/16 | ⬜ 待审 |
 | F8 | 健康检查 | ⬜ 待开始 | — | — |
 | F9 | Agent 调度器 | ⬜ 待开始 | — | — |
 | F10 | Counter | ⬜ 待开始 | — | — |
diff --git a/tests/test_health.py b/tests/test_health.py
new file mode 100644
index 0000000..4699dcb
--- /dev/null
+++ b/tests/test_health.py
@@ -0,0 +1,255 @@
+"""F8 健康检查单元测试
+
+按 test-plan-v2.6.md §F8：
+- T1: 正常场景（P0）
+- T2: 僵尸检测（P0）
+- T3: 恢复场景（P0）
+- T4: 多项目独立检测（P1）
+"""
+
+import asyncio
+import json
+import pytest
+from pathlib import Path
+
+from src.blackboard.operations import Blackboard
+from src.blackboard.models import Task
+from src.daemon.health import HealthChecker
+from src.daemon.ticker import Ticker
+from src.blackboard.registry import ProjectRegistry
+
+
+@pytest.fixture
+def db_path(tmp_path):
+    return tmp_path / "test-proj" / "blackboard.db"
+
+
+@pytest.fixture
+def bb(db_path):
+    return Blackboard(db_path)
+
+
+@pytest.fixture
+def checker():
+    return HealthChecker(zombie_threshold=3)
+
+
+# ---------------------------------------------------------------------------
+# T1: 正常场景
+# ---------------------------------------------------------------------------
+
+class TestNormal:
+    def test_healthy_project(self, checker, db_path, bb):
+        """有真实变更 → 健康"""
+        # 写一个真实事件
+        bb.create_task(Task(id="t1", title="T", status="pending", assigned_by="d"))
+
+        result = checker.check("test-proj", db_path, tick_num=1)
+        assert result["healthy"] is True
+        assert result["zombie"] is False
+
+    def test_no_zombie_alert_under_threshold(self, checker, db_path, bb):
+        """stale < threshold → 不告警"""
+        for i in range(2):
+            result = checker.check("test-proj", db_path, tick_num=i + 1)
+            assert result["healthy"] is True
+            assert result["zombie"] is False
+
+    def test_stale_ticks_increment(self, checker, db_path, bb):
+        """每次无变更 tick 递增 stale_ticks"""
+        r1 = checker.check("test-proj", db_path, tick_num=1)
+        assert r1["stale_ticks"] == 1
+
+        r2 = checker.check("test-proj", db_path, tick_num=2)
+        assert r2["stale_ticks"] == 2
+
+    def test_no_db_is_healthy(self, checker, tmp_path):
+        """无 DB 文件 → 健康（不报错）"""
+        result = checker.check("no-db", tmp_path / "nonexistent.db", tick_num=1)
+        assert result["healthy"] is True
+
+
+# ---------------------------------------------------------------------------
+# T2: 僵尸检测
+# ---------------------------------------------------------------------------
+
+class TestZombieDetection:
+    def test_zombie_after_threshold(self, checker, db_path, bb):
+        """达到 threshold → 僵尸告警"""
+        # 连续 threshold 次 tick 无真实变更
+        for i in range(3):
+            result = checker.check("test-proj", db_path, tick_num=i + 1)
+
+        assert result["zombie"] is True
+        assert result["healthy"] is False
+        assert result["alert_written"] is True
+
+    def test_zombie_writes_observation(self, checker, db_path, bb):
+        """僵尸告警写入 observations 表"""
+        for i in range(3):
+            checker.check("test-proj", db_path, tick_num=i + 1)
+
+        from src.blackboard.queries import Queries
+        queries = Queries(db_path)
+        # 查 observations（排除 events 里的 daemon_tick）
+        conn = queries._conn()
+        try:
+            rows = conn.execute(
+                "SELECT * FROM observations WHERE observer='daemon'"
+            ).fetchall()
+        finally:
+            conn.close()
+
+        assert len(rows) >= 1
+        body = json.loads(rows[0]["body"])
+        assert body["type"] == "zombie_detected"
+        assert body["stale_ticks"] == 3
+
+    def test_zombie_writes_event(self, checker, db_path, bb):
+        """僵尸告警写入 events 表"""
+        for i in range(3):
+            checker.check("test-proj", db_path, tick_num=i + 1)
+
+        from src.blackboard.queries import Queries
+        queries = Queries(db_path)
+        events = queries.recent_events(limit=20)
+        zombie_events = [e for e in events
+                         if e["event_type"] == "agent_zombie_detected"]
+        assert len(zombie_events) >= 1
+
+    def test_no_duplicate_alert(self, checker, db_path, bb):
+        """已告警后不再重复告警"""
+        for i in range(5):
+            result = checker.check("test-proj", db_path, tick_num=i + 1)
+
+        # 只在第一次达到 threshold 时告警
+        assert result["alert_written"] is False  # 后续 tick 不再重复
+        assert result["zombie"] is True
+
+    def test_custom_threshold(self, db_path, bb):
+        """自定义 threshold"""
+        checker = HealthChecker(zombie_threshold=5)
+        for i in range(4):
+            result = checker.check("test-proj", db_path, tick_num=i + 1)
+            assert result["healthy"] is True
+
+        r5 = checker.check("test-proj", db_path, tick_num=5)
+        assert r5["zombie"] is True
+
+
+# ---------------------------------------------------------------------------
+# T3: 恢复场景
+# ---------------------------------------------------------------------------
+
+class TestRecovery:
+    def test_recovery_after_real_event(self, checker, db_path, bb):
+        """僵尸后有真实变更 → 告警解除"""
+        # 触发僵尸
+        for i in range(3):
+            checker.check("test-proj", db_path, tick_num=i + 1)
+
+        # 写一个真实事件（非 daemon_tick）
+        bb.create_task(Task(id="t1", title="T", status="pending", assigned_by="d"))
+
+        # 下一次 check
+        result = checker.check("test-proj", db_path, tick_num=4)
+        assert result["healthy"] is True
+        assert result["resolved"] is True
+
+    def test_recovery_resets_stale(self, checker, db_path, bb):
+        """恢复后 stale_ticks 归零"""
+        for i in range(3):
+            checker.check("test-proj", db_path, tick_num=i + 1)
+
+        bb.create_task(Task(id="t1", title="T", status="pending", assigned_by="d"))
+        result = checker.check("test-proj", db_path, tick_num=4)
+        assert result["stale_ticks"] == 0
+
+    def test_recovery_then_zombie_again(self, checker, db_path, bb):
+        """恢复后再次变僵尸"""
+        # 第一次僵尸
+        for i in range(3):
+            checker.check("test-proj", db_path, tick_num=i + 1)
+        # 恢复
+        bb.create_task(Task(id="t1", title="T", status="pending", assigned_by="d"))
+        checker.check("test-proj", db_path, tick_num=4)
+        # 再次僵尸
+        for i in range(3):
+            r = checker.check("test-proj", db_path, tick_num=5 + i)
+        assert r["zombie"] is True
+
+    def test_recovery_writes_info_observation(self, checker, db_path, bb):
+        """恢复时写 info observation"""
+        for i in range(3):
+            checker.check("test-proj", db_path, tick_num=i + 1)
+
+        bb.create_task(Task(id="t1", title="T", status="pending", assigned_by="d"))
+        checker.check("test-proj", db_path, tick_num=4)
+
+        from src.blackboard.queries import Queries
+        queries = Queries(db_path)
+        conn = queries._conn()
+        try:
+            rows = conn.execute(
+                "SELECT * FROM observations WHERE observer='daemon' "
+                "ORDER BY created_at DESC"
+            ).fetchall()
+        finally:
+            conn.close()
+
+        # 最新一条应该是 resolved
+        body = json.loads(rows[0]["body"])
+        assert body["type"] == "zombie_resolved"
+        assert rows[0]["severity"] == "info"
+
+
+# ---------------------------------------------------------------------------
+# T4: 多项目独立检测（P1）
+# ---------------------------------------------------------------------------
+
+class TestMultiProject:
+    def test_independent_detection(self, tmp_path):
+        """项目 A 僵尸不影响项目 B"""
+        checker = HealthChecker(zombie_threshold=3)
+
+        # 项目 A
+        db_a = tmp_path / "a" / "blackboard.db"
+        bb_a = Blackboard(db_a)
+
+        # 项目 B（有真实事件）
+        db_b = tmp_path / "b" / "blackboard.db"
+        bb_b = Blackboard(db_b)
+        bb_b.create_task(Task(id="b1", title="B", status="pending", assigned_by="d"))
+
+        for i in range(3):
+            checker.check("a", db_a, tick_num=i + 1)
+            checker.check("b", db_b, tick_num=i + 1)
+
+        status_a = checker.get_status("a")
+        status_b = checker.get_status("b")
+
+        assert status_a["is_zombie"] is True
+        assert status_b["is_zombie"] is False
+
+    def test_independent_recovery(self, tmp_path):
+        """项目 A 恢复不影响项目 B"""
+        checker = HealthChecker(zombie_threshold=2)
+
+        db_a = tmp_path / "a" / "blackboard.db"
+        bb_a = Blackboard(db_a)
+
+        db_b = tmp_path / "b" / "blackboard.db"
+        bb_b = Blackboard(db_b)
+
+        # 两个都变僵尸
+        for i in range(2):
+            checker.check("a", db_a, tick_num=i + 1)
+            checker.check("b", db_b, tick_num=i + 1)
+
+        # 只恢复 A
+        bb_a.create_task(Task(id="a1", title="A", status="pending", assigned_by="d"))
+        checker.check("a", db_a, tick_num=3)
+        checker.check("b", db_b, tick_num=3)
+
+        assert checker.get_status("a")["is_zombie"] is False
+        assert checker.get_status("b")["is_zombie"] is True