clarify datetime range is inclusive stac-utils#1382

pystac/common_metadata.py

@@ -85,7 +85,11 @@ def description(self, v: str | None) -> None:
     # Date and Time Range
     @property
     def start_datetime(self) -> datetime | None:
-        """Get or set the object's start_datetime."""
+        """Get or set the object's start_datetime.
+        
+        Note:
+            ``start_datetime`` is an inclusive datetime.
+        """
         return utils.map_opt(
             utils.str_to_datetime, self._get_field("start_datetime", str)
         )
@@ -96,7 +100,11 @@ def start_datetime(self, v: datetime | None) -> None:
 
     @property
     def end_datetime(self) -> datetime | None:
-        """Get or set the item's end_datetime."""
+        """Get or set the item's end_datetime.
+        
+        Note:
+            ``end_datetime`` is an inclusive datetime.
+        """
         return utils.map_opt(
             utils.str_to_datetime, self._get_field("end_datetime", str)
         )

pystac/item.py

@@ -51,9 +51,9 @@ class Item(STACObject, Assets):
         datetime : datetime associated with this item. If None,
             a start_datetime and end_datetime must be supplied.
         properties : A dictionary of additional metadata for the item.
-        start_datetime : Optional start datetime, part of common metadata. This value
+        start_datetime : Optional inclusive start datetime, part of common metadata. This value
             will override any `start_datetime` key in properties.
-        end_datetime : Optional end datetime, part of common metadata. This value
+        end_datetime : Optional inclusive end datetime, part of common metadata. This value
             will override any `end_datetime` key in properties.
         stac_extensions : Optional list of extensions the Item implements.
         href : Optional HREF for this item, which be set as the item's