diff --git a/Doc/library/json.rst b/Doc/library/json.rst
--- a/Doc/library/json.rst
+++ b/Doc/library/json.rst
@@ -585,32 +585,34 @@ specified, :attr:`sys.stdin` and :attr:`
     }
     $ echo '{1.2:3.4}' | python -m json.tool
     Expecting property name enclosed in double quotes: line 1 column 2 (char 1)
 
 
 Command line options
 ^^^^^^^^^^^^^^^^^^^^
 
-.. cmdoption:: [<infile>]
+.. cmdoption:: infile
 
    The JSON file to be validated or pretty-printed::
 
       $ python -m json.tool mp_films.json
       [
           {
               "title": "And Now for Something Completely Different",
               "year": 1971
           },
           {
               "title": "Monty Python and the Holy Grail",
               "year": 1975
           }
       ]
 
-.. cmdoption:: [<outfile>]
+   If *infile* is not specified, read from :attr:`sys.stdin`.
+
+.. cmdoption:: outfile
 
    Write the output of the *infile* to the given *outfile*. Otherwise, write it
    to :attr:`sys.stdout`.
 
 .. cmdoption:: -h, --help
 
    Show the help message.