diff --git a/nanobot/agent/tools/calendar.py b/nanobot/agent/tools/calendar.py
index 4943952..3f655ad 100644
--- a/nanobot/agent/tools/calendar.py
+++ b/nanobot/agent/tools/calendar.py
@@ -179,7 +179,34 @@ class CalendarTool(Tool):
                     coerced["action"] = "list_events" if value == "calendar" else value
                     coerced.pop(key, None)
                     break
-        
+
+        # Models often omit `action` and pass only a range ("this week", "1 week") under a junk key.
+        if not coerced.get("action"):
+            _known_actions = {
+                "list_events",
+                "create_event",
+                "delete_event",
+                "delete_events",
+                "update_event",
+                "check_availability",
+                "calendar",
+            }
+            _create_keys = {"title", "start_time", "end_time", "event_id", "event_ids", "description", "location", "attendees"}
+            if len(coerced) == 1:
+                only_k, only_v = next(iter(coerced.items()))
+                if only_k == "time_min" and isinstance(only_v, str):
+                    coerced["action"] = "list_events"
+                elif isinstance(only_v, str) and only_k not in _create_keys:
+                    if only_v in _known_actions:
+                        coerced["action"] = "list_events" if only_v == "calendar" else only_v
+                        coerced.pop(only_k, None)
+                    else:
+                        coerced = {"action": "list_events", "time_min": only_v}
+                else:
+                    coerced["action"] = "list_events"
+            else:
+                coerced = {**coerced, "action": "list_events"}
+
         return coerced
 
     @property