diff --git a/nanobot/agent/loop.py b/nanobot/agent/loop.py
index 4a9947e4a..e137a61c0 100644
--- a/nanobot/agent/loop.py
+++ b/nanobot/agent/loop.py
@@ -528,6 +528,12 @@ class AgentLoop:
             effective_key = UNIFIED_SESSION_KEY
         else:
             effective_key = f"{channel}:{chat_id}"
+        effective_key = self._tool_context_session_key(
+            channel=channel,
+            chat_id=chat_id,
+            metadata=metadata,
+            session_key=effective_key,
+        )
 
         request_ctx = RequestContext(
             channel=channel,
@@ -542,6 +548,24 @@ class AgentLoop:
             if tool and isinstance(tool, ContextAware):
                 tool.set_context(request_ctx)
 
+    def _tool_context_session_key(
+        self,
+        *,
+        channel: str,
+        chat_id: str,
+        metadata: dict | None,
+        session_key: str,
+    ) -> str:
+        """Return the session key tools should use for ownership-scoped resources."""
+        if (
+            self._unified_session
+            and channel == "websocket"
+            and (metadata or {}).get("webui") is True
+            and chat_id
+        ):
+            return f"websocket:{chat_id}"
+        return session_key
+
     @staticmethod
     def _runtime_chat_id(msg: InboundMessage) -> str:
         """Return the chat id shown in runtime metadata for the model."""
diff --git a/tests/test_tool_contextvars.py b/tests/test_tool_contextvars.py
index a72296d67..3826ba37f 100644
--- a/tests/test_tool_contextvars.py
+++ b/tests/test_tool_contextvars.py
@@ -4,6 +4,7 @@ import asyncio
 
 import pytest
 
+from nanobot.agent.loop import AgentLoop
 from nanobot.agent.tools.context import RequestContext
 from nanobot.agent.tools.cron import CronTool
 from nanobot.agent.tools.message import MessageTool
@@ -243,6 +244,35 @@ async def test_cron_tool_basic_set_context_and_execute(tmp_path) -> None:
     assert jobs[0].payload.session_key == "wechat:user-789"
 
 
+@pytest.mark.asyncio
+async def test_webui_cron_tool_uses_visible_session_under_unified_session(tmp_path) -> None:
+    """WebUI-created automations should attach to the visible thread, not unified memory."""
+    tool = CronTool(CronService(tmp_path / "jobs.json"))
+
+    class _Tools:
+        tool_names = ["cron"]
+
+        def get(self, name: str):
+            return tool if name == "cron" else None
+
+    loop = object.__new__(AgentLoop)
+    loop._unified_session = True
+    loop.tools = _Tools()
+    loop._set_tool_context(
+        "websocket",
+        "chat-123",
+        metadata={"webui": True},
+        session_key="unified:default",
+    )
+
+    result = await tool.execute(action="add", message="standup", every_seconds=300)
+    assert result.startswith("Created job")
+
+    jobs = tool._cron.list_jobs()
+    assert len(jobs) == 1
+    assert jobs[0].payload.session_key == "websocket:chat-123"
+
+
 @pytest.mark.asyncio
 async def test_cron_tool_no_context_returns_error(tmp_path) -> None:
     """Without set_context, add should fail with a clear error."""