diff --git a/cron/scheduler.py b/cron/scheduler.py
index 359069966195..84d2fadd2605 100644
--- a/cron/scheduler.py
+++ b/cron/scheduler.py
@@ -434,8 +434,15 @@ def _resolve_single_delivery_target(job: dict, deliver_value: str) -> Optional[d
 
     if deliver_value == "origin":
         if origin:
+            platform = origin["platform"]
+            # WebUI surfaces cron runs by reading the local session DB —
+            # no external gateway delivery is needed. Returning None
+            # treats it like "local", avoiding "unknown platform 'webui'"
+            # errors (#45360).
+            if platform.lower() == "webui":
+                return None
             return {
-                "platform": origin["platform"],
+                "platform": platform,
                 "chat_id": str(origin["chat_id"]),
                 "thread_id": origin.get("thread_id"),
             }
diff --git a/tests/cron/test_scheduler.py b/tests/cron/test_scheduler.py
index fd445de8ca6a..c5915166acca 100644
--- a/tests/cron/test_scheduler.py
+++ b/tests/cron/test_scheduler.py
@@ -87,6 +87,28 @@ def test_origin_delivery_preserves_thread_id(self):
             "thread_id": "17585",
         }
 
+    def test_webui_origin_platform_returns_none(self):
+        """WebUI reads from local session DB — no gateway delivery needed (#45360)."""
+        job = {
+            "deliver": "origin",
+            "origin": {
+                "platform": "webui",
+                "chat_id": "session-abc",
+            },
+        }
+        assert _resolve_delivery_target(job) is None
+
+    def test_webui_origin_platform_case_insensitive(self):
+        """Platform name comparison should be case-insensitive."""
+        job = {
+            "deliver": "origin",
+            "origin": {
+                "platform": "WebUI",
+                "chat_id": "session-abc",
+            },
+        }
+        assert _resolve_delivery_target(job) is None
+
     @pytest.mark.parametrize(
         ("platform", "env_var", "chat_id"),
         [