-**Syntax**: ``<xpath>/<target-node>/[@<leaf-name>=<leaf-value>]``
- - ``xpath``: The xpath to the parent of the target node including all ancestors.
- - ``target-node``: The name of the (list) node which elements will queried.
+Each CPS path expression need to start with an 'absolute' or 'descendant' xpath.
+
+absolute-path
+-------------
+
+**Syntax**: ``'/' <container-name> ( '[' <list-key> ']' )? ( '/' <containerName> ( '[' <list-key> ']' )? )*``
+
+ - ``container name``: Any yang container or list.
+ - ``list-key``: One or more key-value pairs, each preceded by the ``@`` symbol, combined using the ``and`` keyword.
+ - The above van repeated any number of times.
+
+**Examples**
+ - ``/shops/bookstore``
+ - ``/shops/bookstore/categories[@code='1']/books``
+ - ``/shops/bookstore/categories[@code='1']/books/book[@title='2001: A Space Odyssey']``
+
+**Limitations**
+ - Absolute paths must start with the top element (data node) as per the model tree.
+ - Each list reference must include a valid instance reference to the key for that list. Except when it is the last element.
+ - The Absolute path to list with integer key will not work. It needs to be surrounded with a single quote ([@code='1'])
+ as if it is a string. This will be fixed in `CPS-961 <https://jira.onap.org/browse/CPS-961>`_
+
+descendant-path
+---------------
+
+**Syntax**: ``'//' <container-name> ( '[' <list-key> ']' )? ( '/' <containerName> ( '[' <list-key> ']' )? )*``
+
+ - The syntax of a descendant path is identical to a absolute path except that it is preceded by a double slash ``//``.
+
+**Examples**
+ - ``//bookstore``
+ - ``//categories[@code='1']/books``
+ - ``//bookstore/categories``
+
+**Limitations**
+ - Each list reference must include a valid instance reference to the key for that list. Except when it is the last element.
+
+leaf-conditions
+---------------
+
+**Syntax**: ``<xpath> '[' @<leaf-name1> '=' <leaf-value1> ( ' and ' @<leaf-name> '=' <leaf-value> )* ']'``
+ - ``xpath``: Absolute or descendant or xpath to the (list) node which elements will be queried.