diff --git a/.yardopts b/.yardopts
new file mode 100644
index 0000000..f03ab31
--- /dev/null
+++ b/.yardopts
@@ -0,0 +1 @@
+--api public --hide-void-return --markup markdown
diff --git a/lib/pundit.rb b/lib/pundit.rb
index ed3ba3a..95e73bd 100644
--- a/lib/pundit.rb
+++ b/lib/pundit.rb
@@ -6,10 +6,17 @@ require "active_support/core_ext/object/blank"
 require "active_support/core_ext/module/introspection"
 require "active_support/dependencies/autoload"
 
+# @api public
 module Pundit
   SUFFIX = "Policy"
 
+  # @api private
+  module Generators; end
+
+  # @api private
   class Error < StandardError; end
+
+  # Error that will be raiser when authorization has failed
   class NotAuthorizedError < Error
     attr_reader :query, :record, :policy
 
@@ -27,13 +34,30 @@ module Pundit
       super(message)
     end
   end
+
+  # Error that will be raised if a controller action has not called the
+  # `authorize` or `skip_authorization` methods.
   class AuthorizationNotPerformedError < Error; end
+
+  # Error that will be raised if a controller action has not called the
+  # `policy_scope` or `skip_policy_scope` methods.
   class PolicyScopingNotPerformedError < AuthorizationNotPerformedError; end
+
+  # Error that will be raised if a policy or policy scope is not defined.
   class NotDefinedError < Error; end
 
   extend ActiveSupport::Concern
 
   class << self
+    # Retrieves the policy for the given record, initializing it with the
+    # record and user and finally throwing an error if the user is not
+    # authorized to perform the given action.
+    #
+    # @param user [Object] the user that initiated the action
+    # @param record [Object] the object we're checking permissions of
+    # @param record [Symbol] the query method to check on the policy (e.g. `:show?`)
+    # @raise [NotAuthorizedError] if the given query method returned false
+    # @return [true] Always returns true
     def authorize(user, record, query)
       policy = policy!(user, record)
 
@@ -44,25 +68,52 @@ module Pundit
       true
     end
 
+    # Retrieves the policy scope for the given record.
+    #
+    # @see https://github.com/elabs/pundit#scopes
+    # @param user [Object] the user that initiated the action
+    # @param record [Object] the object we're retrieving the policy scope for
+    # @return [Scope{#resolve}, nil] instance of scope class which can resolve to a scope
     def policy_scope(user, scope)
       policy_scope = PolicyFinder.new(scope).scope
       policy_scope.new(user, scope).resolve if policy_scope
     end
 
+    # Retrieves the policy scope for the given record.
+    #
+    # @see https://github.com/elabs/pundit#scopes
+    # @param user [Object] the user that initiated the action
+    # @param record [Object] the object we're retrieving the policy scope for
+    # @raise [NotDefinedError] if the policy scope cannot be found
+    # @return [Scope{#resolve}] instance of scope class which can resolve to a scope
     def policy_scope!(user, scope)
       PolicyFinder.new(scope).scope!.new(user, scope).resolve
     end
 
+    # Retrieves the policy for the given record.
+    #
+    # @see https://github.com/elabs/pundit#policies
+    # @param user [Object] the user that initiated the action
+    # @param record [Object] the object we're retrieving the policy for
+    # @return [Object, nil] instance of policy class with query methods
     def policy(user, record)
       policy = PolicyFinder.new(record).policy
       policy.new(user, record) if policy
     end
 
+    # Retrieves the policy for the given record.
+    #
+    # @see https://github.com/elabs/pundit#policies
+    # @param user [Object] the user that initiated the action
+    # @param record [Object] the object we're retrieving the policy for
+    # @raise [NotDefinedError] if the policy cannot be found
+    # @return [Object] instance of policy class with query methods
     def policy!(user, record)
       PolicyFinder.new(record).policy!.new(user, record)
     end
   end
 
+  # @api private
   module Helper
     def policy_scope(scope)
       pundit_policy_scope(scope)
@@ -93,22 +144,48 @@ module Pundit
     end
   end
 
+  # @return [Boolean] whether authorization has been performed, i.e. whether
+  #                   one {#authorize} or {#skip_authorization} has been called
   def pundit_policy_authorized?
     !!@_pundit_policy_authorized
   end
 
+  # @return [Boolean] whether policy scoping has been performed, i.e. whether
+  #                   one {#policy_scope} or {#skip_policy_scope} has been called
   def pundit_policy_scoped?
     !!@_pundit_policy_scoped
   end
 
+  # Raises an error if authorization has not been performed, usually used as an
+  # `after_action` filter to prevent programmer error in forgetting to call
+  # {#authorize} or {#skip_authorization}.
+  #
+  # @see https://github.com/elabs/pundit#ensuring-policies-are-used
+  # @raise [AuthorizationNotPerformedError] if authorization has not been performed
+  # @return [void]
   def verify_authorized
     raise AuthorizationNotPerformedError, self.class unless pundit_policy_authorized?
   end
 
+  # Raises an error if policy scoping has not been performed, usually used as an
+  # `after_action` filter to prevent programmer error in forgetting to call
+  # {#policy_scope} or {#skip_policy_scope} in index actions.
+  #
+  # @see https://github.com/elabs/pundit#ensuring-policies-are-used
+  # @raise [AuthorizationNotPerformedError] if policy scoping has not been performed
+  # @return [void]
   def verify_policy_scoped
     raise PolicyScopingNotPerformedError, self.class unless pundit_policy_scoped?
   end
 
+  # Retrieves the policy for the given record, initializing it with the record
+  # and current user and finally throwing an error if the user is not
+  # authorized to perform the given action.
+  #
+  # @param record [Object] the object we're checking permissions of
+  # @param record [Symbol, nil] the query method to check on the policy (e.g. `:show?`)
+  # @raise [NotAuthorizedError] if the given query method returned false
+  # @return [true] Always returns true
   def authorize(record, query = nil)
     query ||= params[:action].to_s + "?"
 
@@ -123,23 +200,50 @@ module Pundit
     true
   end
 
+  # Allow this action not to perform authorization.
+  #
+  # @see https://github.com/elabs/pundit#ensuring-policies-are-used
+  # @return [void]
   def skip_authorization
     @_pundit_policy_authorized = true
   end
 
+  # Allow this action not to perform policy scoping.
+  #
+  # @see https://github.com/elabs/pundit#ensuring-policies-are-used
+  # @return [void]
   def skip_policy_scope
     @_pundit_policy_scoped = true
   end
 
+  # Retrieves the policy scope for the given record.
+  #
+  # @see https://github.com/elabs/pundit#scopes
+  # @param record [Object] the object we're retrieving the policy scope for
+  # @return [Scope{#resolve}, nil] instance of scope class which can resolve to a scope
   def policy_scope(scope)
     @_pundit_policy_scoped = true
     pundit_policy_scope(scope)
   end
 
+  # Retrieves the policy for the given record.
+  #
+  # @see https://github.com/elabs/pundit#policies
+  # @param record [Object] the object we're retrieving the policy for
+  # @return [Object, nil] instance of policy class with query methods
   def policy(record)
     policies[record] ||= Pundit.policy!(pundit_user, record)
   end
 
+  # Retrieves a set of permitted attributes from the policy by instantiating
+  # the policy class for the given record and calling `permitted_attributes` on
+  # it, or `permitted_attributes_for_{action}` if it is defined. It then infers
+  # what key the record should have in the params hash and retrieves the
+  # permitted attributes from the params hash under that key.
+  #
+  # @see https://github.com/elabs/pundit#strong-parameters
+  # @param record [Object] the object we're retrieving permitted attributes for
+  # @return [Hash{String => Object}] the permitted attributes
   def permitted_attributes(record, action = params[:action])
     param_key = PolicyFinder.new(record).param_key
     policy = policy(record)
@@ -151,14 +255,25 @@ module Pundit
     params.require(param_key).permit(policy.public_send(method_name))
   end
 
+  # Cache of policies. You should not rely on this method.
+  #
+  # @api private
   def policies
     @_pundit_policies ||= {}
   end
 
+  # Cache of policy scope. You should not rely on this method.
+  #
+  # @api private
   def policy_scopes
     @_pundit_policy_scopes ||= {}
   end
 
+  # Hook method which allows customizing which user is passed to policies and
+  # scopes initialized by {#authorize}, {#policy} and {#policy_scope}.
+  #
+  # @see https://github.com/elabs/pundit#customize-pundit-user
+  # @return [Object] the user object to be used with pundit
   def pundit_user
     current_user
   end
diff --git a/lib/pundit/policy_finder.rb b/lib/pundit/policy_finder.rb
index a6c0ce7..6072f36 100644
--- a/lib/pundit/policy_finder.rb
+++ b/lib/pundit/policy_finder.rb
@@ -10,13 +10,13 @@ module Pundit
   class PolicyFinder
     attr_reader :object
 
-    # @param object [any]
+    # @param object [any] the object to find policy and scope classes for
     #
     def initialize(object)
       @object = object
     end
 
-    # @return [nil, Scope{#resolve}]
+    # @return [nil, Scope{#resolve}] scope class which can resolve to a scope
     # @see https://github.com/elabs/pundit#scopes
     # @example
     #   scope = finder.scope #=> UserPolicy::Scope
@@ -43,7 +43,7 @@ module Pundit
       nil
     end
 
-    # @return [Scope{#resolve}]
+    # @return [Scope{#resolve}] scope class which can resolve to a scope
     # @raise [NotDefinedError] if scope could not be determined
     #
     def scope!
@@ -73,9 +73,6 @@ module Pundit
 
   private
 
-    # @return [String] policy class name
-    # @api public
-    #
     def find
       if object.nil?
         nil