diff --git a/.gitignore b/.gitignore
index afa1ad1..701c6dd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 __pycache__/
 .ruff_cache/
 .venv/
+.pytest_cache/
diff --git a/Dockerfile b/Dockerfile
index 700b8ab..e08d4ba 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -28,6 +28,9 @@ VOLUME ["/data"]
 
 EXPOSE 80
 
+HEALTHCHECK --start-period=5s --start-interval=1s CMD \
+    test "$(curl -fsS "http://127.0.0.1:$PORT/health")" = "ok"
+
 STOPSIGNAL SIGINT
 
 CMD ["/entrypoint.sh"]
diff --git a/src/healthcheck.py b/src/healthcheck.py
new file mode 100644
index 0000000..b38e59a
--- /dev/null
+++ b/src/healthcheck.py
@@ -0,0 +1,18 @@
+import os
+import urllib.request
+
+
+def main() -> int:
+    port = os.environ.get("PORT", "80")
+    url = f"http://127.0.0.1:{port}/health"
+
+    try:
+        with urllib.request.urlopen(url, timeout=2) as resp:
+            body = resp.read().decode("utf-8").strip()
+            return 0 if resp.status == 200 and body == "ok" else 1
+    except Exception:
+        return 1
+
+
+if __name__ == "__main__":
+    exit(main())
diff --git a/src/providers/base.py b/src/providers/base.py
index 478ab53..5f9cdc6 100644
--- a/src/providers/base.py
+++ b/src/providers/base.py
@@ -71,7 +71,7 @@ class Provider(ABC):
         """Usage percent when provider may switch active account/token."""
         return None
 
-    def should_prepare_standby(self, usage_percent: int) -> bool:
+    def should_prepare_standby(self) -> bool:
         """Whether standby preparation should be triggered for current usage."""
         return False
 
diff --git a/src/providers/chatgpt/provider.py b/src/providers/chatgpt/provider.py
index 603c247..b536611 100644
--- a/src/providers/chatgpt/provider.py
+++ b/src/providers/chatgpt/provider.py
@@ -122,14 +122,14 @@ class ChatGPTProvider(Provider):
                 return True
             return await self._create_next_account_under_lock()
 
-    def should_prepare_standby(self, usage_percent: int) -> bool:
-        return usage_percent >= self.prepare_threshold and bool(load_next_tokens())
+    def should_prepare_standby(self) -> bool:
+        return bool(load_next_tokens())
 
     async def ensure_standby_account(
         self,
         usage_percent: int,
     ) -> None:
-        if self.should_prepare_standby(usage_percent):
+        if usage_percent >= self.prepare_threshold:
             await self.ensure_next_account()
 
     async def maybe_switch_active_account(self, usage_percent: int) -> bool:
diff --git a/src/server.py b/src/server.py
index be2e905..171b5c8 100644
--- a/src/server.py
+++ b/src/server.py
@@ -47,7 +47,7 @@ def should_trigger_standby_prepare(provider_name: str, usage_percent: int) -> bo
     provider = PROVIDERS.get(provider_name)
     if not provider:
         return False
-    return provider.should_prepare_standby(usage_percent)
+    return provider.should_prepare_standby()
 
 
 async def ensure_provider_token_ready(provider_name: str):
@@ -86,7 +86,7 @@ async def ensure_standby_task(provider_name: str, usage_percent: int, reason: st
     if not provider:
         return
 
-    if not provider.should_prepare_standby(usage_percent):
+    if not provider.should_prepare_standby():
         return
 
     try:
@@ -188,6 +188,11 @@ async def token_handler(request: web.Request) -> web.Response:
     )
 
 
+async def health_handler(request: web.Request) -> web.Response:
+    del request
+    return web.Response(text="ok")
+
+
 async def on_startup(app: web.Application):
     del app
     for provider_name in PROVIDERS:
@@ -208,6 +213,7 @@ def create_app() -> web.Application:
     app = web.Application(middlewares=[request_log_middleware])
     app.on_startup.append(on_startup)
     app.on_cleanup.append(on_cleanup)
+    app.router.add_get("/health", health_handler)
     app.router.add_get("/{provider}/token", token_handler)
     app.router.add_get("/token", token_handler)
     return app
diff --git a/tests/test_server_unit.py b/tests/test_server_unit.py
index 68b3030..8ebefb8 100644
--- a/tests/test_server_unit.py
+++ b/tests/test_server_unit.py
@@ -34,8 +34,8 @@ class FakeProvider(Provider):
     def prepare_threshold(self) -> int:
         return self._prepare_threshold
 
-    def should_prepare_standby(self, usage_percent: int) -> bool:
-        return usage_percent >= self.prepare_threshold
+    def should_prepare_standby(self) -> bool:
+        return False
 
     @property
     def name(self) -> str:
@@ -113,6 +113,12 @@ def test_token_handler_unknown_provider(monkeypatch):
     assert resp.status == 404
 
 
+def test_health_handler_ok():
+    resp = asyncio.run(server.health_handler(object()))
+    assert resp.status == 200
+    assert resp.text == "ok"
+
+
 def test_token_handler_success(monkeypatch):
     provider = FakeProvider()
     monkeypatch.setattr(server, "PROVIDERS", {"fake": provider})