diff --git a/README.md b/README.md
index 34f21f2..d1a3b13 100644
--- a/README.md
+++ b/README.md
@@ -231,6 +231,7 @@ integration:
 - **Active Model** select entity controls the model override used for chat-card and Assist requests.
 - If no model is selected, the gateway default is used.
 - Assist conversation IDs are conservatively namespaced by agent ID so different agents do not accidentally share the same conversation context.
+- When a signed-in Home Assistant user is known, the Assist session key carries it (`assist_user_<id>:<conversation>`), so the agent can tell who is speaking while each conversation keeps its own session.
 
 ### Voice provider usage
 
diff --git a/custom_components/openclaw/conversation.py b/custom_components/openclaw/conversation.py
index 701134c..7e92abb 100644
--- a/custom_components/openclaw/conversation.py
+++ b/custom_components/openclaw/conversation.py
@@ -40,7 +40,11 @@
 )
 from .coordinator import OpenClawCoordinator
 from .exposure import apply_context_policy, build_exposed_entities_context
-from .helpers import extract_text_recursive, scope_agent_session_id
+from .helpers import (
+    assist_base_session_id,
+    extract_text_recursive,
+    scope_agent_session_id,
+)
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -247,22 +251,13 @@ def _resolve_conversation_id(
             return configured_session_id
 
         agent_suffix = self._normalize_optional_text(agent_id)
-
-        if user_input.conversation_id:
-            return scope_agent_session_id(user_input.conversation_id, agent_suffix)
-
         context = getattr(user_input, "context", None)
-        user_id = getattr(context, "user_id", None)
-        if user_id:
-            base_id = f"assist_user_{user_id}"
-            return scope_agent_session_id(base_id, agent_suffix)
-
-        device_id = getattr(user_input, "device_id", None)
-        if device_id:
-            base_id = f"assist_device_{device_id}"
-            return scope_agent_session_id(base_id, agent_suffix)
-
-        return scope_agent_session_id("assist_default", agent_suffix)
+        base_id = assist_base_session_id(
+            user_input.conversation_id,
+            getattr(context, "user_id", None),
+            getattr(user_input, "device_id", None),
+        )
+        return scope_agent_session_id(base_id, agent_suffix)
 
     def _normalize_optional_text(self, value: Any) -> str | None:
         """Return a stripped string or None for blank values."""
diff --git a/custom_components/openclaw/helpers.py b/custom_components/openclaw/helpers.py
index 0edd733..2108445 100644
--- a/custom_components/openclaw/helpers.py
+++ b/custom_components/openclaw/helpers.py
@@ -12,6 +12,32 @@ def scope_agent_session_id(base_id: str, agent_id: str | None) -> str:
     return f"agent:{agent_id}:{base_id}"
 
 
+def assist_base_session_id(
+    conversation_id: str | None,
+    user_id: str | None,
+    device_id: str | None,
+) -> str:
+    """Pick the unscoped Assist session id without dropping the signed-in user.
+
+    The pipeline sends a conversation id on every turn, which used to hide the user.
+    """
+    if user_id:
+        user_base = f"assist_user_{user_id}"
+        if not conversation_id:
+            return user_base
+        if (
+            conversation_id.startswith(f"{user_base}:")
+            or f":{user_base}:" in conversation_id
+        ):
+            return conversation_id
+        return f"{user_base}:{conversation_id}"
+    if conversation_id:
+        return conversation_id
+    if device_id:
+        return f"assist_device_{device_id}"
+    return "assist_default"
+
+
 def resolve_active_model(
     preferred_model: str | None,
     available_models: list[str],
diff --git a/tests/test_helpers.py b/tests/test_helpers.py
index f012724..a66efd7 100644
--- a/tests/test_helpers.py
+++ b/tests/test_helpers.py
@@ -36,6 +36,60 @@ def test_is_idempotent_for_an_already_scoped_key(self) -> None:
         )
 
 
+class AssistBaseSessionIdTests(unittest.TestCase):
+    """Keep the signed-in HA user in the key when HA sends a conversation id."""
+
+    def test_user_and_conversation_are_both_kept(self) -> None:
+        self.assertEqual(
+            helpers.assist_base_session_id("01m4hf34nxm64w74ab60v9pbrc", "abc", "dev1"),
+            "assist_user_abc:01m4hf34nxm64w74ab60v9pbrc",
+        )
+
+    def test_follow_up_turn_is_not_prefixed_twice(self) -> None:
+        self.assertEqual(
+            helpers.assist_base_session_id("assist_user_abc:01m4", "abc", None),
+            "assist_user_abc:01m4",
+        )
+        self.assertEqual(
+            helpers.assist_base_session_id("agent:home:assist_user_abc:01m4", "abc", None),
+            "agent:home:assist_user_abc:01m4",
+        )
+
+    def test_user_without_conversation(self) -> None:
+        self.assertEqual(
+            helpers.assist_base_session_id(None, "abc", "dev1"),
+            "assist_user_abc",
+        )
+
+    def test_conversation_id_without_a_user(self) -> None:
+        self.assertEqual(
+            helpers.assist_base_session_id("01m4hf34nxm64w74ab60v9pbrc", None, "dev1"),
+            "01m4hf34nxm64w74ab60v9pbrc",
+        )
+
+    def test_device_without_user_or_conversation(self) -> None:
+        self.assertEqual(
+            helpers.assist_base_session_id(None, None, "dev1"),
+            "assist_device_dev1",
+        )
+
+    def test_default_when_nothing_is_known(self) -> None:
+        self.assertEqual(
+            helpers.assist_base_session_id(None, None, None),
+            "assist_default",
+        )
+
+    def test_scoped_follow_up_stays_stable(self) -> None:
+        first = helpers.scope_agent_session_id(
+            helpers.assist_base_session_id("01m4", "abc", None), "home"
+        )
+        again = helpers.scope_agent_session_id(
+            helpers.assist_base_session_id(first, "abc", None), "home"
+        )
+        self.assertEqual(first, "agent:home:assist_user_abc:01m4")
+        self.assertEqual(again, first)
+
+
 class ResolveActiveModelTests(unittest.TestCase):
     """Protect an explicit HA model choice across coordinator refreshes."""