Document the pipe_cmd plugin

doc/source/plugins/index.rst

@@ -210,6 +210,11 @@ Plugin index
 
         Reverse everything you say.
 
+    Pipe Command
+        :ref:`Documentation <pipecmd-plugin>`
+
+        Send commands to poezio through a named pipe.
+
     Shuffle
         :ref:`Documentation <shuffle-plugin>`
 
@@ -279,3 +284,4 @@ Plugin index
     autocorrect
     irc
     change_title
+    pipe_cmd

doc/source/plugins/pipe_cmd.rst

@@ -0,0 +1,6 @@
+.. _pipecmd-plugin:
+
+Pipe Command
+============
+
+.. automodule:: pipe_cmd

plugins/pipe_cmd.py

@@ -2,6 +2,20 @@
 
 This plugins allows commands to be sent to poezio via a named pipe.
 
+You can run the same commands that you would in the poezio input
+(e.g. ``echo '/message toto@example.tld Hi' >> /tmp/poezio.fifo``).
+
+Configuration
+-------------
+
+.. glossary::
+    :sorted:
+
+    pipename
+        **Default:** :file:`/tmp/poezio.fifo`
+
+        The path to the fifo which will receive commands.
+
 """