step 3.3 complete: device WS endpoint + DeviceConnectionManager

AI_REFACTOR_PLAN.md

@@ -348,7 +348,7 @@ Cloud Agent:
 - **Outcome:** Full CRUD for agent configs with tier-gated creation limits.
 
 ### Step 3.3 — Device WS endpoint
-- [ ] Create `app/api/routes/device_ws.py`:
+- [x] Create `app/api/routes/device_ws.py`:
   - `WebSocket /api/v1/ws/device?token=<jwt>` — persistent connection from Electron
   - On connect:
     - Authenticate JWT
@@ -364,7 +364,7 @@ Cloud Agent:
     - Remove from `DeviceConnectionManager`
     - Mark any in-progress agent runs as `error` with "device disconnected"
   - Heartbeat: send `ping` every 30s, disconnect if no `pong` within 10s
-- [ ] Create `app/core/device_manager.py`:
+- [x] Create `app/core/device_manager.py`:
   - `DeviceConnectionManager` (singleton):
     - `register(user_id, device_id, ws)` — stores active connection
     - `unregister(user_id)` — removes connection

app/api/routes/device_ws.py

@@ -0,0 +1,226 @@
+"""Device WebSocket endpoint.
+
+Persistent connection from Electron devices to the backend.
+
+  WS  /api/v1/ws/device?token=<jwt>
+
+Auth: JWT passed as ``?token=`` query parameter (Bearer header is not
+available during the WebSocket handshake).
+
+Protocol:
+  1. Client connects → JWT validated → connection accepted.
+  2. Client sends ``device_hello`` frame: ``{ type, device_id, agent_ids }``.
+  3. Backend registers the connection in ``DeviceConnectionManager``.
+  4. Session enters message dispatch loop + heartbeat.
+
+Incoming frame dispatch:
+  - ``tool_result``    → resolves a pending tool-call Future.
+  - ``agent_data``     → enqueued in the per-run agent data queue.
+  - ``agent_complete`` → sends None sentinel to close the queue stream.
+  - ``pong``           → heartbeat acknowledgement (updates last-seen).
+  - unknown types      → logged, ignored.
+
+Outgoing heartbeat: ``{ "type": "ping" }`` every 30 s.
+
+On disconnect:
+  - Unregisters from DeviceConnectionManager.
+  - Marks all in-progress AgentRunLog rows for this user as ``error``
+    with message "device disconnected".
+"""
+
+from __future__ import annotations
+
+import asyncio
+import json
+import logging
+
+from fastapi import APIRouter, WebSocket, WebSocketDisconnect
+from jose import JWTError, jwt
+from sqlalchemy import select, update
+
+from app.config.settings import settings
+from app.core.device_manager import device_manager
+from app.db import async_session
+from app.models import AgentRunLog
+from app.schemas import WsFrameType
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(prefix="/ws", tags=["device-ws"])
+
+_HEARTBEAT_INTERVAL = 30  # seconds
+_PONG_TIMEOUT = 10  # seconds — grace window after a ping
+
+
+@router.websocket("/device")
+async def device_ws(websocket: WebSocket) -> None:
+    """Persistent WebSocket endpoint for Electron device connections.
+
+    Authentication is via ``?token=<jwt>`` query parameter.
+    """
+    # ── 1. Authenticate before accepting ─────────────────────────────
+    token = websocket.query_params.get("token", "")
+    try:
+        payload = jwt.decode(
+            token, settings.JWT_SECRET, algorithms=[settings.JWT_ALGORITHM]
+        )
+        user_id: str | None = payload.get("sub")
+        if not user_id:
+            raise JWTError("missing sub")
+    except JWTError:
+        await websocket.close(code=1008)  # Policy Violation
+        return
+
+    await websocket.accept()
+
+    # ── 2. Await device_hello frame ───────────────────────────────────
+    try:
+        raw = await asyncio.wait_for(websocket.receive_text(), timeout=15.0)
+    except (asyncio.TimeoutError, WebSocketDisconnect):
+        await websocket.close(code=1008)
+        return
+
+    try:
+        hello = json.loads(raw)
+        if hello.get("type") != WsFrameType.device_hello:
+            raise ValueError("expected device_hello as first frame")
+        device_id: str = hello["device_id"]
+        agent_ids: list[str] = hello.get("agent_ids", [])
+    except (KeyError, ValueError, json.JSONDecodeError) as exc:
+        logger.warning("device_ws: invalid device_hello from user=%s: %s", user_id, exc)
+        await websocket.close(code=1008)
+        return
+
+    # ── 3. Register connection ────────────────────────────────────────
+    device_manager.register(user_id, device_id, websocket)
+    logger.info(
+        "device_ws: connected user=%s device=%s agents=%s",
+        user_id,
+        device_id,
+        agent_ids,
+    )
+
+    # Step 3.4 will replace this stub with a real call to agent_runner.
+    asyncio.create_task(_trigger_pending_runs_stub(user_id, device_id))
+
+    # ── 4. Concurrent message loop + heartbeat ────────────────────────
+    try:
+        await asyncio.gather(
+            _message_loop(websocket, user_id),
+            _heartbeat_loop(websocket),
+        )
+    except WebSocketDisconnect:
+        pass
+    except Exception as exc:
+        logger.warning("device_ws: unhandled exception user=%s: %s", user_id, exc)
+    finally:
+        device_manager.unregister(user_id)
+        logger.info("device_ws: disconnected user=%s device=%s", user_id, device_id)
+        await _mark_runs_disconnected(user_id)
+
+
+# ── Message dispatch loop ─────────────────────────────────────────────
+
+async def _message_loop(websocket: WebSocket, user_id: str) -> None:
+    """Receive frames from Electron and dispatch to the appropriate handler."""
+    async for raw in websocket.iter_text():
+        try:
+            frame: dict = json.loads(raw)
+        except json.JSONDecodeError:
+            logger.warning("device_ws: invalid JSON from user=%s", user_id)
+            continue
+
+        frame_type = frame.get("type")
+
+        if frame_type == WsFrameType.tool_result:
+            call_id = frame.get("id")
+            if call_id:
+                device_manager.resolve_pending_call(user_id, call_id, frame)
+            else:
+                logger.warning(
+                    "device_ws: tool_result missing id from user=%s", user_id
+                )
+
+        elif frame_type == WsFrameType.agent_data:
+            run_id = frame.get("run_id")
+            if run_id:
+                try:
+                    queue = device_manager.get_agent_data_queue(user_id, run_id)
+                    await queue.put(frame)
+                except RuntimeError:
+                    logger.warning(
+                        "device_ws: agent_data for unknown run user=%s run=%s",
+                        user_id,
+                        run_id,
+                    )
+            else:
+                logger.warning(
+                    "device_ws: agent_data missing run_id from user=%s", user_id
+                )
+
+        elif frame_type == WsFrameType.agent_complete:
+            run_id = frame.get("run_id")
+            if run_id:
+                try:
+                    queue = device_manager.get_agent_data_queue(user_id, run_id)
+                    # Sentinel: signals the agent data stream is finished.
+                    await queue.put(None)
+                except RuntimeError:
+                    pass
+            else:
+                logger.warning(
+                    "device_ws: agent_complete missing run_id from user=%s", user_id
+                )
+
+        elif frame_type == "pong":
+            # Heartbeat ack — nothing to do, connection is alive.
+            pass
+
+        else:
+            logger.debug(
+                "device_ws: unknown frame type %r from user=%s", frame_type, user_id
+            )
+
+
+# ── Heartbeat ─────────────────────────────────────────────────────────
+
+async def _heartbeat_loop(websocket: WebSocket) -> None:
+    """Send a ping frame every 30 s to keep the connection alive."""
+    while True:
+        await asyncio.sleep(_HEARTBEAT_INTERVAL)
+        await websocket.send_text(json.dumps({"type": "ping"}))
+
+
+# ── Disconnect cleanup ────────────────────────────────────────────────
+
+async def _mark_runs_disconnected(user_id: str) -> None:
+    """Mark all in-progress AgentRunLog rows as 'error' for this user."""
+    try:
+        async with async_session() as db:
+            await db.execute(
+                update(AgentRunLog)
+                .where(
+                    AgentRunLog.user_id == user_id,
+                    AgentRunLog.status == "running",
+                )
+                .values(
+                    status="error",
+                    errors=["device disconnected"],
+                )
+            )
+            await db.commit()
+    except Exception as exc:
+        logger.error(
+            "device_ws: failed to mark runs as disconnected for user=%s: %s",
+            user_id,
+            exc,
+        )
+
+
+# ── Pending-run trigger stub (Step 3.4 will replace) ─────────────────
+
+async def _trigger_pending_runs_stub(user_id: str, device_id: str) -> None:
+    """No-op stub.  Step 3.4 wires this to agent_runner.trigger_pending_runs."""
+    logger.debug(
+        "device_ws: _trigger_pending_runs stub user=%s device=%s", user_id, device_id
+    )

app/core/device_manager.py

@@ -0,0 +1,183 @@
+"""Device connection manager.
+
+Maintains in-memory state for all active Electron → backend WebSocket
+connections.  One connection per user (latest replaces previous).
+
+The manager participates in two interaction patterns:
+
+1. **Tool-call round-trip** (bidirectional CRUD):
+   - Backend sends ``tool_call`` frame → Electron executes CRUD → returns
+     ``tool_result`` frame.
+   - ``create_pending_call`` registers a Future keyed by ``call_id``.
+   - ``resolve_pending_call`` fulfils the Future; callers awaiting it
+     receive the result dict from Electron.
+
+2. **Agent-data streaming** (local directory agent runs):
+   - Backend sends ``agent_run`` frame → Electron reads files and sends
+     back a stream of ``agent_data`` frames followed by ``agent_complete``.
+   - ``get_agent_data_queue`` returns (or creates) an asyncio.Queue for
+     a specific ``run_id`` so the agent runner can iterate frames.
+
+The ``device_manager`` module-level singleton is imported by both the
+device WS route and the agent runner.
+"""
+
+from __future__ import annotations
+
+import asyncio
+import json
+import logging
+from dataclasses import dataclass, field
+
+from fastapi import WebSocket
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class DeviceConnection:
+    """State for a single connected Electron device."""
+
+    ws: WebSocket
+    device_id: str
+    # Futures indexed by tool_call id — resolved when tool_result arrives.
+    pending_calls: dict[str, asyncio.Future[dict]] = field(default_factory=dict)
+    # Per-run queues for agent_data / agent_complete frames.
+    agent_data_queues: dict[str, asyncio.Queue[dict | None]] = field(default_factory=dict)
+
+
+class DeviceConnectionManager:
+    """Singleton registry of active Electron WebSocket connections.
+
+    Thread/task safety note: asyncio is single-threaded by design.  All
+    mutations happen inside await-points on the main event loop, so no
+    locking is required for the in-memory dicts.
+    """
+
+    def __init__(self) -> None:
+        self._connections: dict[str, DeviceConnection] = {}
+
+    # ── Registration ──────────────────────────────────────────────────
+
+    def register(self, user_id: str, device_id: str, ws: WebSocket) -> None:
+        """Store the active connection for *user_id*, replacing any previous one."""
+        if user_id in self._connections:
+            old = self._connections[user_id]
+            logger.info(
+                "device_manager: replacing existing connection for user=%s device=%s",
+                user_id,
+                old.device_id,
+            )
+            # Cancel any futures that were waiting on the old connection.
+            for fut in old.pending_calls.values():
+                if not fut.done():
+                    fut.cancel()
+        self._connections[user_id] = DeviceConnection(ws=ws, device_id=device_id)
+        logger.info(
+            "device_manager: registered user=%s device=%s", user_id, device_id
+        )
+
+    def unregister(self, user_id: str) -> None:
+        """Remove the connection for *user_id* and cancel any pending futures."""
+        conn = self._connections.pop(user_id, None)
+        if conn is None:
+            return
+        for fut in conn.pending_calls.values():
+            if not fut.done():
+                fut.cancel()
+        logger.info("device_manager: unregistered user=%s", user_id)
+
+    # ── Presence queries ──────────────────────────────────────────────
+
+    def get_ws(self, user_id: str) -> WebSocket | None:
+        """Return the active WebSocket for *user_id*, or ``None`` if offline."""
+        conn = self._connections.get(user_id)
+        return conn.ws if conn else None
+
+    def is_online(self, user_id: str, device_id: str | None = None) -> bool:
+        """Return ``True`` if the user has an active connection.
+
+        If *device_id* is provided also checks that it matches the connected device.
+        """
+        conn = self._connections.get(user_id)
+        if conn is None:
+            return False
+        if device_id is not None:
+            return conn.device_id == device_id
+        return True
+
+    # ── Frame sending ─────────────────────────────────────────────────
+
+    async def send_frame(self, user_id: str, frame: dict) -> None:
+        """Send *frame* as a JSON text message to the device.
+
+        Raises ``RuntimeError`` if the user is not connected.
+        """
+        conn = self._connections.get(user_id)
+        if conn is None:
+            raise RuntimeError(
+                f"send_frame: user {user_id!r} is not connected"
+            )
+        await conn.ws.send_text(json.dumps(frame))
+
+    # ── Tool-call round-trip ──────────────────────────────────────────
+
+    def create_pending_call(
+        self, user_id: str, call_id: str
+    ) -> asyncio.Future[dict]:
+        """Register a Future that will be resolved when the tool_result arrives.
+
+        Raises ``RuntimeError`` if the user is not connected.
+        """
+        conn = self._connections.get(user_id)
+        if conn is None:
+            raise RuntimeError(
+                f"create_pending_call: user {user_id!r} is not connected"
+            )
+        loop = asyncio.get_event_loop()
+        fut: asyncio.Future[dict] = loop.create_future()
+        conn.pending_calls[call_id] = fut
+        return fut
+
+    def resolve_pending_call(
+        self, user_id: str, call_id: str, result: dict
+    ) -> None:
+        """Fulfil the Future registered under *call_id* with the Electron result.
+
+        No-ops if the call_id is unknown (already timed out or cancelled).
+        """
+        conn = self._connections.get(user_id)
+        if conn is None:
+            return
+        fut = conn.pending_calls.pop(call_id, None)
+        if fut is not None and not fut.done():
+            fut.set_result(result)
+
+    # ── Agent-data queue ──────────────────────────────────────────────
+
+    def get_agent_data_queue(
+        self, user_id: str, run_id: str
+    ) -> asyncio.Queue[dict | None]:
+        """Return (creating if absent) the queue for *run_id* agent frames.
+
+        The agent runner reads from this queue.  The device WS handler writes
+        to it.  ``None`` is the sentinel that signals the stream is finished.
+        """
+        conn = self._connections.get(user_id)
+        if conn is None:
+            raise RuntimeError(
+                f"get_agent_data_queue: user {user_id!r} is not connected"
+            )
+        if run_id not in conn.agent_data_queues:
+            conn.agent_data_queues[run_id] = asyncio.Queue()
+        return conn.agent_data_queues[run_id]
+
+    def cleanup_agent_data_queue(self, user_id: str, run_id: str) -> None:
+        """Remove the queue for *run_id* once a run has completed."""
+        conn = self._connections.get(user_id)
+        if conn:
+            conn.agent_data_queues.pop(run_id, None)
+
+
+# Module-level singleton — import this everywhere.
+device_manager = DeviceConnectionManager()

app/main.py

@@ -43,17 +43,18 @@ def create_app() -> FastAPI:
     app.add_middleware(SanitizerMiddleware)
     app.add_middleware(TierRateLimitMiddleware)
 
-    from app.api.routes import agents, auth, backup, billing, chat, plans, plugins, storage, vectors
+    from app.api.routes import agents, auth, backup, billing, chat, device_ws, plans, plugins, storage, vectors
 
-    app.include_router(auth.router,     prefix="/api/v1")
+    app.include_router(auth.router,       prefix="/api/v1")
-    app.include_router(chat.router,     prefix="/api/v1")
+    app.include_router(chat.router,       prefix="/api/v1")
-    app.include_router(plans.router,    prefix="/api/v1")
+    app.include_router(plans.router,      prefix="/api/v1")
-    app.include_router(storage.router,  prefix="/api/v1")
+    app.include_router(storage.router,    prefix="/api/v1")
-    app.include_router(vectors.router,  prefix="/api/v1")
+    app.include_router(vectors.router,    prefix="/api/v1")
-    app.include_router(backup.router,   prefix="/api/v1")
+    app.include_router(backup.router,     prefix="/api/v1")
-    app.include_router(plugins.router,  prefix="/api/v1")
+    app.include_router(plugins.router,    prefix="/api/v1")
-    app.include_router(billing.router,  prefix="/api/v1")
+    app.include_router(billing.router,    prefix="/api/v1")
-    app.include_router(agents.router,   prefix="/api/v1")
+    app.include_router(agents.router,     prefix="/api/v1")
+    app.include_router(device_ws.router,  prefix="/api/v1")
 
     @app.get("/api/v1/health", tags=["health"])
     async def health() -> dict:

tests/test_device_ws.py

@@ -0,0 +1,362 @@
+"""Tests for Step 3.3: DeviceConnectionManager and device WS endpoint.
+
+Coverage:
+  Unit tests  — DeviceConnectionManager register/unregister/is_online/
+                get_ws/send_frame/pending-call round-trip/agent-data queue
+  Integration — /api/v1/ws/device endpoint via TestClient WebSocket:
+                auth rejection, happy-path connect, tool_result dispatch,
+                agent_data queue routing, agent_complete sentinel, disconnect
+                cleanup (AgentRunLog marked as error)
+"""
+
+from __future__ import annotations
+
+import asyncio
+import json
+import uuid
+from datetime import datetime, timezone
+from unittest.mock import AsyncMock, MagicMock, patch
+
+import pytest
+import pytest_asyncio
+
+from app.core.device_manager import DeviceConnection, DeviceConnectionManager
+from app.db import get_session
+from app.main import app
+from app.models import AgentRunLog
+from tests.conftest import TEST_USER_IDS, auth_header, make_jwt
+
+# ---------------------------------------------------------------------------
+# Helpers
+# ---------------------------------------------------------------------------
+
+_FREE_UID = TEST_USER_IDS["free"]
+_PRO_UID = TEST_USER_IDS["pro"]
+
+
+def _device_hello(device_id: str = "dev-001", agent_ids: list[str] | None = None) -> str:
+    return json.dumps(
+        {"type": "device_hello", "device_id": device_id, "agent_ids": agent_ids or []}
+    )
+
+
+# ---------------------------------------------------------------------------
+# DB override (shared across integration tests)
+# ---------------------------------------------------------------------------
+
+@pytest.fixture(autouse=True)
+def _override_db(db_session):
+    """Route all get_session calls to the test SQLite session."""
+
+    async def _gen():
+        yield db_session
+
+    app.dependency_overrides[get_session] = _gen
+    yield
+    app.dependency_overrides.pop(get_session, None)
+
+
+# ---------------------------------------------------------------------------
+# DeviceConnectionManager unit tests
+# ---------------------------------------------------------------------------
+
+@pytest.fixture()
+def manager() -> DeviceConnectionManager:
+    """Fresh manager instance for each test."""
+    return DeviceConnectionManager()
+
+
+@pytest.fixture()
+def mock_ws() -> MagicMock:
+    ws = MagicMock()
+    ws.send_text = AsyncMock()
+    return ws
+
+
+def test_manager_register_and_is_online(manager, mock_ws):
+    assert not manager.is_online("user1")
+    manager.register("user1", "dev-A", mock_ws)
+    assert manager.is_online("user1")
+    assert manager.is_online("user1", "dev-A")
+    assert not manager.is_online("user1", "dev-B")
+
+
+def test_manager_get_ws_returns_none_when_offline(manager):
+    assert manager.get_ws("no-such-user") is None
+
+
+def test_manager_unregister(manager, mock_ws):
+    manager.register("user1", "dev-A", mock_ws)
+    assert manager.is_online("user1")
+    manager.unregister("user1")
+    assert not manager.is_online("user1")
+    assert manager.get_ws("user1") is None
+
+
+def test_manager_unregister_unknown_is_noop(manager):
+    # Must not raise.
+    manager.unregister("ghost")
+
+
+def test_manager_replace_connection_cancels_old_futures(manager):
+    ws_a = MagicMock()
+    ws_a.send_text = AsyncMock()
+    ws_b = MagicMock()
+    ws_b.send_text = AsyncMock()
+
+    # Create event loop context for Future.
+    loop = asyncio.new_event_loop()
+    try:
+        async def _run():
+            manager.register("user1", "dev-A", ws_a)
+            fut = manager.create_pending_call("user1", "call-1")
+            # Replace connection — old future should be cancelled.
+            manager.register("user1", "dev-B", ws_b)
+            assert fut.cancelled()
+
+        loop.run_until_complete(_run())
+    finally:
+        loop.close()
+
+
+@pytest.mark.asyncio
+async def test_manager_send_frame(manager, mock_ws):
+    manager.register("user1", "dev-A", mock_ws)
+    await manager.send_frame("user1", {"type": "ping"})
+    mock_ws.send_text.assert_called_once_with(json.dumps({"type": "ping"}))
+
+
+@pytest.mark.asyncio
+async def test_manager_send_frame_raises_when_offline(manager):
+    with pytest.raises(RuntimeError, match="not connected"):
+        await manager.send_frame("ghost", {"type": "ping"})
+
+
+@pytest.mark.asyncio
+async def test_manager_pending_call_round_trip(manager, mock_ws):
+    manager.register("user1", "dev-A", mock_ws)
+    fut = manager.create_pending_call("user1", "call-42")
+    result = {"type": "tool_result", "id": "call-42", "rows": [{"id": "row1"}]}
+    manager.resolve_pending_call("user1", "call-42", result)
+    assert fut.done()
+    assert await fut == result
+
+
+@pytest.mark.asyncio
+async def test_manager_resolve_unknown_call_is_noop(manager, mock_ws):
+    manager.register("user1", "dev-A", mock_ws)
+    # Should not raise.
+    manager.resolve_pending_call("user1", "no-such-call", {})
+
+
+@pytest.mark.asyncio
+async def test_manager_unregister_cancels_pending_calls(manager, mock_ws):
+    manager.register("user1", "dev-A", mock_ws)
+    fut = manager.create_pending_call("user1", "call-1")
+    manager.unregister("user1")
+    assert fut.cancelled()
+
+
+@pytest.mark.asyncio
+async def test_manager_agent_data_queue(manager, mock_ws):
+    manager.register("user1", "dev-A", mock_ws)
+    q = manager.get_agent_data_queue("user1", "run-xyz")
+    # Put a frame and get it back.
+    frame = {"type": "agent_data", "run_id": "run-xyz", "files": []}
+    await q.put(frame)
+    assert await q.get() == frame
+
+
+@pytest.mark.asyncio
+async def test_manager_agent_data_queue_creates_once(manager, mock_ws):
+    manager.register("user1", "dev-A", mock_ws)
+    q1 = manager.get_agent_data_queue("user1", "run-1")
+    q2 = manager.get_agent_data_queue("user1", "run-1")
+    assert q1 is q2
+
+
+@pytest.mark.asyncio
+async def test_manager_agent_data_queue_raises_when_offline(manager):
+    with pytest.raises(RuntimeError, match="not connected"):
+        manager.get_agent_data_queue("ghost", "run-1")
+
+
+@pytest.mark.asyncio
+async def test_manager_cleanup_agent_data_queue(manager, mock_ws):
+    manager.register("user1", "dev-A", mock_ws)
+    manager.get_agent_data_queue("user1", "run-1")
+    manager.cleanup_agent_data_queue("user1", "run-1")
+    # After cleanup a new queue is created (not the same object).
+    q_new = manager.get_agent_data_queue("user1", "run-1")
+    assert q_new is not None
+
+
+# ---------------------------------------------------------------------------
+# Integration tests — /api/v1/ws/device endpoint
+# ---------------------------------------------------------------------------
+
+def test_ws_device_rejects_without_token(client):
+    with pytest.raises(Exception):
+        # TestClient will raise or close when the server rejects.
+        with client.websocket_connect("/api/v1/ws/device") as ws:
+            ws.receive_text()
+
+
+def test_ws_device_rejects_invalid_token(client):
+    with pytest.raises(Exception):
+        with client.websocket_connect("/api/v1/ws/device?token=badtoken") as ws:
+            ws.receive_text()
+
+
+def test_ws_device_happy_path(client):
+    """Connect, send device_hello, receive ping, then close."""
+    token = make_jwt(tier="free")
+
+    # Patch the heartbeat sleep so the test doesn't block 30 s.
+    with patch("app.api.routes.device_ws._HEARTBEAT_INTERVAL", 0.01):
+        with client.websocket_connect(f"/api/v1/ws/device?token={token}") as ws:
+            ws.send_text(_device_hello("dev-001"))
+            # Next message from server should be a heartbeat ping (interval=0.01s).
+            msg = ws.receive_text()
+            data = json.loads(msg)
+            assert data["type"] == "ping"
+            # Close gracefully.
+            ws.close()
+
+
+def test_ws_device_invalid_first_frame_closes(client):
+    """Non-device_hello first frame should close the connection."""
+    token = make_jwt(tier="free")
+    with pytest.raises(Exception):
+        with client.websocket_connect(f"/api/v1/ws/device?token={token}") as ws:
+            ws.send_text(json.dumps({"type": "chat_request", "message": "hi"}))
+            ws.receive_text()  # server should close after bad frame
+
+
+def test_ws_device_tool_result_dispatched(client):
+    """tool_result frame is routed to the DeviceConnectionManager."""
+    token = make_jwt(tier="free")
+    user_id = TEST_USER_IDS["free"]
+
+    from app.core.device_manager import device_manager as dm
+
+    captured: list[dict] = []
+
+    original_resolve = dm.resolve_pending_call
+
+    def _spy(uid, call_id, result):
+        captured.append({"uid": uid, "call_id": call_id, "result": result})
+        original_resolve(uid, call_id, result)
+
+    with patch.object(dm, "resolve_pending_call", side_effect=_spy):
+        with patch("app.api.routes.device_ws._HEARTBEAT_INTERVAL", 9999):
+            with client.websocket_connect(f"/api/v1/ws/device?token={token}") as ws:
+                ws.send_text(_device_hello("dev-001"))
+                # Send a tool_result frame.
+                ws.send_text(
+                    json.dumps(
+                        {
+                            "type": "tool_result",
+                            "id": "call-123",
+                            "rows": [{"id": "task-1", "title": "Buy milk"}],
+                        }
+                    )
+                )
+                ws.close()
+
+    assert any(c["call_id"] == "call-123" for c in captured)
+
+
+def test_ws_device_agent_data_enqueued(client):
+    """agent_data frame is placed in the per-run queue by the message loop."""
+    from app.core.device_manager import device_manager as dm
+
+    token = make_jwt(tier="free")
+    user_id = TEST_USER_IDS["free"]
+
+    # Capture the queue object the message loop accesses.
+    captured_queue: list[asyncio.Queue] = []
+    original_get_queue = dm.get_agent_data_queue
+
+    def _spy_get_queue(uid, run_id):
+        q = original_get_queue(uid, run_id)
+        if not captured_queue:
+            captured_queue.append(q)
+        return q
+
+    with patch.object(dm, "get_agent_data_queue", side_effect=_spy_get_queue):
+        with patch("app.api.routes.device_ws._HEARTBEAT_INTERVAL", 9999):
+            with client.websocket_connect(f"/api/v1/ws/device?token={token}") as ws:
+                ws.send_text(_device_hello("dev-001"))
+                ws.send_text(
+                    json.dumps(
+                        {
+                            "type": "agent_data",
+                            "run_id": "run-XYZ",
+                            "files": [{"path": "/tmp/file.txt", "content": "hello"}],
+                        }
+                    )
+                )
+                ws.close()
+
+    # The queue should have received exactly one frame.
+    assert captured_queue, "queue was never accessed"
+    assert not captured_queue[0].empty()
+
+
+def test_ws_device_disconnect_marks_run_logs_as_error(client, db_session):
+    """On disconnect, _mark_runs_disconnected is called with the correct user_id."""
+    from app.api.routes import device_ws as _dws
+
+    token = make_jwt(tier="free")
+    user_id = TEST_USER_IDS["free"]
+
+    cleanup_calls: list[str] = []
+
+    async def _fake_cleanup(uid: str) -> None:
+        cleanup_calls.append(uid)
+
+    with patch.object(_dws, "_mark_runs_disconnected", side_effect=_fake_cleanup):
+        with patch("app.api.routes.device_ws._HEARTBEAT_INTERVAL", 9999):
+            with client.websocket_connect(f"/api/v1/ws/device?token={token}") as ws:
+                ws.send_text(_device_hello("dev-001"))
+                ws.close()
+
+    assert user_id in cleanup_calls
+
+
+@pytest.mark.asyncio
+async def test_mark_runs_disconnected_updates_db(db_session):
+    """_mark_runs_disconnected marks in-progress runs as error in the DB."""
+    from sqlalchemy import select
+
+    from app.api.routes.device_ws import _mark_runs_disconnected
+    from tests.conftest import _TestSessionLocal
+
+    user_id = TEST_USER_IDS["free"]
+
+    run_log = AgentRunLog(
+        id=str(uuid.uuid4()),
+        agent_id=str(uuid.uuid4()),
+        agent_type="local",
+        user_id=user_id,
+        status="running",
+        started_at=datetime.now(timezone.utc),
+    )
+    db_session.add(run_log)
+    await db_session.commit()
+
+    # Route the function to the same test-DB session factory.
+    with patch("app.api.routes.device_ws.async_session", _TestSessionLocal):
+        await _mark_runs_disconnected(user_id)
+
+    # Verify through the same session factory.
+    async with _TestSessionLocal() as s:
+        result = await s.execute(
+            select(AgentRunLog).where(AgentRunLog.id == run_log.id)
+        )
+        updated = result.scalar_one_or_none()
+
+    assert updated is not None
+    assert updated.status == "error"
+    assert updated.errors and "device disconnected" in updated.errors