diff --git a/src/mqtt_home/emqx_api.py b/src/mqtt_home/emqx_api.py
new file mode 100644
index 0000000..1ff8066
--- /dev/null
+++ b/src/mqtt_home/emqx_api.py
@@ -0,0 +1,41 @@
+import httpx
+from typing import Any
+
+from mqtt_home.config import Settings
+
+
+class EmqxApiClient:
+    def __init__(self, settings: Settings):
+        self._client = httpx.AsyncClient(
+            base_url=settings.emqx_api_url,
+            auth=(settings.emqx_api_key, settings.emqx_api_secret),
+            timeout=10.0,
+        )
+
+    async def close(self):
+        await self._client.aclose()
+
+    async def get_broker_status(self) -> dict[str, Any]:
+        resp = await self._client.get("/status")
+        resp.raise_for_status()
+        return resp.json().get("data", {})
+
+    async def get_metrics(self) -> dict[str, Any]:
+        resp = await self._client.get("/metrics")
+        resp.raise_for_status()
+        return resp.json().get("data", {})
+
+    async def get_clients(self, limit: int = 100) -> list[dict[str, Any]]:
+        resp = await self._client.get("/clients", params={"limit": limit})
+        resp.raise_for_status()
+        return resp.json().get("data", [])
+
+    async def get_subscriptions(self, limit: int = 100) -> list[dict[str, Any]]:
+        resp = await self._client.get("/subscriptions", params={"limit": limit})
+        resp.raise_for_status()
+        return resp.json().get("data", [])
+
+    async def get_topics(self, limit: int = 100) -> list[dict[str, Any]]:
+        resp = await self._client.get("/topics", params={"limit": limit})
+        resp.raise_for_status()
+        return resp.json().get("data", [])
diff --git a/src/mqtt_home/schemas.py b/src/mqtt_home/schemas.py
new file mode 100644
index 0000000..0c8d7d4
--- /dev/null
+++ b/src/mqtt_home/schemas.py
@@ -0,0 +1,70 @@
+from datetime import datetime
+from typing import Optional
+from pydantic import BaseModel, Field
+
+
+class DeviceCreate(BaseModel):
+    name: str
+    type: str = "switch"
+    protocol: str = "custom"
+    mqtt_topic: str
+    command_topic: Optional[str] = None
+
+
+class DeviceUpdate(BaseModel):
+    name: Optional[str] = None
+    type: Optional[str] = None
+    command_topic: Optional[str] = None
+
+
+class DeviceCommand(BaseModel):
+    payload: str
+
+
+class DeviceResponse(BaseModel):
+    id: str
+    name: str
+    type: str
+    protocol: str
+    mqtt_topic: str
+    command_topic: Optional[str] = None
+    state: Optional[str] = None
+    is_online: bool
+    last_seen: Optional[datetime] = None
+    created_at: datetime
+    updated_at: datetime
+
+    model_config = {"from_attributes": True}
+
+
+class DeviceLogResponse(BaseModel):
+    id: int
+    device_id: str
+    direction: str
+    topic: str
+    payload: str
+    timestamp: datetime
+
+    model_config = {"from_attributes": True}
+
+
+class BrokerClient(BaseModel):
+    clientid: str
+    username: Optional[str] = None
+    ip_address: Optional[str] = None
+    connected: bool
+    keepalive: int
+    proto_ver: Optional[int] = None
+    clean_start: Optional[bool] = None
+
+
+class BrokerTopic(BaseModel):
+    topic: str
+    node: Optional[str] = None
+
+
+class DashboardStats(BaseModel):
+    total_devices: int
+    online_devices: int
+    offline_devices: int
+    recent_logs: list[DeviceLogResponse]
diff --git a/tests/test_emqx_api.py b/tests/test_emqx_api.py
new file mode 100644
index 0000000..2cf61a0
--- /dev/null
+++ b/tests/test_emqx_api.py
@@ -0,0 +1,55 @@
+import pytest
+import httpx
+from unittest.mock import AsyncMock, patch
+
+from mqtt_home.emqx_api import EmqxApiClient
+from mqtt_home.config import Settings
+
+
+@pytest.fixture
+def settings():
+    return Settings(
+        mqtt_host="localhost",
+        emqx_api_url="http://localhost:18083/api/v5",
+        emqx_api_key="test-key",
+        emqx_api_secret="test-secret",
+        database_url="sqlite+aiosqlite:///:memory:",
+    )
+
+
+@pytest.fixture
+def emqx_client(settings):
+    return EmqxApiClient(settings)
+
+
+def _make_response(status_code: int, json_data: dict) -> httpx.Response:
+    request = httpx.Request("GET", "http://localhost:18083/api/v5/test")
+    return httpx.Response(status_code, json=json_data, request=request)
+
+
+async def test_get_broker_status(emqx_client):
+    with patch.object(emqx_client._client, "get", new_callable=AsyncMock) as mock_get:
+        mock_get.return_value = _make_response(
+            200, {"data": {"uptime": 12345, "version": "5.0.0"}}
+        )
+        result = await emqx_client.get_broker_status()
+        assert result["uptime"] == 12345
+
+
+async def test_get_clients(emqx_client):
+    with patch.object(emqx_client._client, "get", new_callable=AsyncMock) as mock_get:
+        mock_get.return_value = _make_response(
+            200, {"data": [{"clientid": "dev1", "connected": True}]}
+        )
+        result = await emqx_client.get_clients()
+        assert len(result) == 1
+        assert result[0]["clientid"] == "dev1"
+
+
+async def test_get_topics(emqx_client):
+    with patch.object(emqx_client._client, "get", new_callable=AsyncMock) as mock_get:
+        mock_get.return_value = _make_response(
+            200, {"data": [{"topic": "home/light"}]}
+        )
+        result = await emqx_client.get_topics()
+        assert len(result) == 1