test: harden timing-fragile test and add cross-tool ContextVar isolation test

Replace asyncio.sleep(0.05) with an asyncio.Event + patched Lock.acquire
to guarantee the waiting task has reached the lock before asserting.  Add
a test confirming LongTaskTool and CompleteGoalTool ContextVars are
isolated, and document the design intent in _GoalToolsMixin.

nanobot/agent/tools/long_task.py

@@ -46,6 +46,9 @@ class _GoalToolsMixin(ContextAware):
     def __init__(self, sessions: SessionManager, bus: Any | None = None) -> None:
         self._sessions = sessions
         self._bus = bus
+        # Each subclass gets its own ContextVar so concurrent tasks across
+        # different tool types (LongTaskTool vs CompleteGoalTool) do not
+        # interfere with each other.
         self._request_ctx: ContextVar[RequestContext | None] = ContextVar(
             f"{self.__class__.__name__}_request_ctx",
             default=None,

tests/agent/test_runner_injections.py

@@ -566,10 +566,21 @@ async def test_waiting_dispatch_does_not_replace_active_pending_queue(tmp_path):
     active_pending = asyncio.Queue(maxsize=1)
     loop._pending_queues[session_key] = active_pending
 
-    waiting = asyncio.create_task(
-        loop._dispatch(InboundMessage(channel="cli", sender_id="u", chat_id="c", content="queued"))
-    )
-    await asyncio.sleep(0.05)
+    waiting_at_lock = asyncio.Event()
+    original_acquire = asyncio.Lock.acquire
+
+    async def _patched_acquire(self, *args, **kwargs):
+        if self is lock:
+            waiting_at_lock.set()
+        return await original_acquire(self, *args, **kwargs)
+
+    with patch.object(asyncio.Lock, "acquire", _patched_acquire):
+        waiting = asyncio.create_task(
+            loop._dispatch(
+                InboundMessage(channel="cli", sender_id="u", chat_id="c", content="queued")
+            )
+        )
+        await asyncio.wait_for(waiting_at_lock.wait(), timeout=2.0)
 
     assert loop._pending_queues[session_key] is active_pending
 

tests/agent/tools/test_long_task.py

@@ -100,6 +100,22 @@ async def test_goal_tools_keep_request_context_per_task(tmp_path):
     assert sm.get_or_create("websocket:b").metadata[GOAL_STATE_KEY]["recap"] == "Done B"
 
 
+@pytest.mark.asyncio
+async def test_goal_tools_context_isolated_across_tool_types(tmp_path):
+    """LongTaskTool and CompleteGoalTool must not share routing context."""
+    sm = SessionManager(tmp_path)
+    lt = LongTaskTool(sessions=sm)
+    cg = CompleteGoalTool(sessions=sm)
+    ctx = RequestContext(channel="websocket", chat_id="a", session_key="websocket:a")
+
+    lt.set_context(ctx)
+    assert cg._request_ctx.get() is None
+
+    cg.set_context(ctx)
+    assert lt._request_ctx.get() is ctx
+    assert cg._request_ctx.get() is ctx
+
+
 @pytest.mark.asyncio
 async def test_long_task_publishes_goal_state_ws_after_save(tmp_path):
     bus = MagicMock()