diff --git a/.github/workflows/plugin-api-v2.yml b/.github/workflows/plugin-api-v2.yml
new file mode 100644
index 0000000..7c1876b
--- /dev/null
+++ b/.github/workflows/plugin-api-v2.yml
@@ -0,0 +1,28 @@
+name: plugin-api-v2
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+permissions:
+  contents: read
+
+jobs:
+  contract:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/checkout@v4
+        with:
+          repository: akashic-plugins/plugin-contracts
+          ref: 24543445c7b99ca63fcd90b5828f754a148b184c
+          path: .plugin-contracts
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.13"
+      - name: Check Plugin API v2
+        env:
+          PYTHONPATH: .plugin-contracts
+        run: python -m akashic_plugin_contracts check plugin.py
diff --git a/plugin.py b/plugin.py
index 437ea39..5dc655f 100644
--- a/plugin.py
+++ b/plugin.py
@@ -28,6 +28,7 @@ def emit(self, event: object) -> None: ...
 
 
 class ObservePlugin(Plugin):
+    api_version = 2
     @classmethod
     def dashboard_module(cls) -> str | None:
         return "dashboard.py"
@@ -47,7 +48,7 @@ def mobile_ui(cls) -> MobileUiContribution:
     name = "observe"
     version = "1.2.0"
 
-    async def initialize(self) -> None:
+    def activate(self) -> None:
         workspace = self.context.workspace
         if workspace is None:
             logger.warning("observe 插件缺少 workspace，跳过加载")
diff --git a/tests/test_plugin.py b/tests/test_plugin.py
index 618cf56..56d0aee 100644
--- a/tests/test_plugin.py
+++ b/tests/test_plugin.py
@@ -93,7 +93,7 @@ async def _run_mobile_turn_observe_seam(
     event_bus.on(TurnCommitted, committed.append)
     try:
         # 1. 用真实 after-reasoning 持久化生成 assistant message ID
-        await plugin.initialize()
+        plugin.activate()
         session = manager.get_or_create("mobile:observe-seam")
         message = InboundMessage(
             channel="mobile",
@@ -180,7 +180,7 @@ async def _run_mobile_turn_observe_seam(
 
 
 @pytest.mark.asyncio
-async def test_observe_plugin_initialize_and_terminate(tmp_path: Path) -> None:
+async def test_observe_plugin_activate_and_terminate(tmp_path: Path) -> None:
     plugin = ObservePlugin()
     scope = PluginScope("observe")
     plugin.context = PluginContext(
@@ -193,7 +193,7 @@ async def test_observe_plugin_initialize_and_terminate(tmp_path: Path) -> None:
         workspace=tmp_path,
         scope=scope,
     )
-    await plugin.initialize()
+    plugin.activate()
     await asyncio.sleep(0.05)
     await plugin.terminate()
     assert await scope.aclose() == []