diff --git a/edmond/plugin.py b/edmond/plugin.py
index de65b13..baf0f71 100644
--- a/edmond/plugin.py
+++ b/edmond/plugin.py
@@ -3,6 +3,32 @@ from pathlib import Path
 
 
 class Plugin:
+    """Base class for the bot plugins.
+
+    This class provides a lot of tools to facilitate the implementation of
+    plugins. Callbacks for all events handled by the IRC library can be
+    implemented here (if the Bot class supports it). Most bot features are put
+    in plugins to avoid cluttering the Bot class, and no plugins should be
+    required for the bot to run; plugins can depend on each other though.
+
+    A plugin loads his basic information from the config file. It can use the
+    bot's runtime values facilities to make runtime values available to other
+    plugins. It can also save data using the Bot's storage feature to be
+    available after a restart.
+
+    Initalisation should be very fast, no network connections or anything. They
+    are initialised before connecting to the server, so their `is_ready` flag is
+    set at that point. The loading order is more or less random, so a plugin
+    cannot assume another has been loaded during initialisation. If it wants to
+    interact with another plugin, the earliest point to do that is in the
+    on_welcome callback which is called after connecting to a server, and can
+    disable itself by setting its own `is_ready` flag to false.
+
+    Plugins can have priorities and calling their callbacks will respect it.
+    For now these levels are used:
+    - 0: default
+    - -3: low, misc parsing of messages, answer to various messages
+    """
 
     REQUIRED_CONFIGS = []
 
@@ -109,7 +135,14 @@ class Plugin:
                 return first_word_and_rest[1].strip()
 
     def should_answer_question(self, message):
-        """Store Question in object and return True if it should answer it."""
+        """Store Question in object and return True if I should answer it.
+
+        To answer a question, the message must start with one of the bot's names
+        and optionally end with one or more question marks (they are discarded).
+        The bot checks that answering conditions are respected, and they cannot
+        be bypassed as with commands. A Question created is checked from the
+        plugin's registered questions and stored in the instance.
+        """
         words = message.split()
         # Is the message addressed to me?
         if len(words) == 0 or words[0].lower() not in self.bot.names:
@@ -139,7 +172,7 @@ class Plugin:
         no_content=False,
         exclude_conditions=None,
     ):
-        """Store Command in object and return True if it should handle it.
+        """Store Command in object and return True if I should handle it.
 
         If no_content is True, the command does not parse command contents and
         put all the command message (without suffix) to the command identifier.
@@ -193,10 +226,10 @@ class Plugin:
         return False
 
     def __parse_command(self, message, no_content=False):
-        """Return a command ID if this message is a command.
+        """Return a parsed Command if this message is a command, None otherwise.
 
         The command raw field is always set. The ident and content fields are
-        not set when no_content is True. The match field is never set by this
+        empty when no_content is True. The match field is never set by this
         method.
         """
         words = message.split()