Update client-request-filter.rst

Applied some rephrasing.

presto-docs/src/main/sphinx/develop/client-request-filter.rst

@@ -3,7 +3,7 @@
 Client Request Filter
 ======================
 
-Presto allows operators to customize the headers used by the Presto runtime to process queries. Some example use cases include customized authentication workflows, or enriching query attributes such as the query source. This can be achieved using the Client Request Filter plugin, which allows control over header customization during query execution.
+Presto allows operators to customize the headers used to process queries. Some example use cases include customized authentication workflows, or enriching query attributes such as the query source. Use the Client Request Filter plugin to control header customization during query execution.
 
 Implementation
 --------------
@@ -17,6 +17,10 @@ The implementation of ``ClientRequestFilterFactory`` must be wrapped as a plugin
 
 After installing a plugin that implements ``ClientRequestFilterFactory`` on the coordinator, the ``AuthenticationFilter`` class passes the ``principal`` object to the request filter, which returns the header values as a map.
 
-Presto uses the request filter to determine whether a header is present in the blocklist. The blocklist includes headers such as ``X-Presto-Transaction-Id``, ``X-Presto-Started-Transaction-Id``, ``X-Presto-Clear-Transaction-Id``, and ``X-Presto-Trace-Token``, which are not allowed to be overridden. For a complete list of headers that may be overridden, please refer to the `Java source`_ (note that the blocklist headers are also listed there, but they are not eligible for overriding).
+Presto uses the request filter to determine whether a header is present in the blocklist. The blocklist includes headers such as ``X-Presto-Transaction-Id``, ``X-Presto-Started-Transaction-Id``, ``X-Presto-Clear-Transaction-Id``, and ``X-Presto-Trace-Token``, which are not allowed to be overridden. 
+
+For a complete list of headers, see the `Java source`_.
+
+Note: The `Java source`_ includes these blocklist headers that are not eligible for overriding. The other headers not mentioned here can be overridden.
 
 .. _Java source: https://github.com/prestodb/presto/blob/master/presto-client/src/main/java/com/facebook/presto/client/PrestoHeaders.java