diff --git a/src/applications/maniphest/config/PhabricatorManiphestConfigOptions.php b/src/applications/maniphest/config/PhabricatorManiphestConfigOptions.php
--- a/src/applications/maniphest/config/PhabricatorManiphestConfigOptions.php
+++ b/src/applications/maniphest/config/PhabricatorManiphestConfigOptions.php
@@ -451,15 +451,20 @@
 EOTEXT
       ));
 
+    $fields_description = $this->deformat(pht(<<<EOTEXT
+List of custom fields for Maniphest tasks.
+
+For details on adding custom fields to Maniphest, see [[ %s | %s ]] in the
+documentation.
+EOTEXT
+      ,
+      PhabricatorEnv::getDoclink('Configuring Custom Fields'),
+      pht('Configuring Custom Fields')));
 
     return array(
       $this->newOption('maniphest.custom-field-definitions', 'wild', array())
         ->setSummary(pht('Custom Maniphest fields.'))
-        ->setDescription(
-          pht(
-            'Array of custom fields for Maniphest tasks. For details on '.
-            'adding custom fields to Maniphest, see "Configuring Custom '.
-            'Fields" in the documentation.'))
+        ->setDescription($fields_description)
         ->addExample($fields_json, pht('Valid setting')),
       $this->newOption('maniphest.fields', $custom_field_type, $default_fields)
         ->setCustomData(id(new ManiphestTask())->getCustomFieldBaseClass())
diff --git a/src/docs/user/configuration/custom_fields.diviner b/src/docs/user/configuration/custom_fields.diviner
--- a/src/docs/user/configuration/custom_fields.diviner
+++ b/src/docs/user/configuration/custom_fields.diviner
@@ -121,6 +121,10 @@
     supported in text, int and remarkup fields (optional).
   - **copy**: If true, this field's value will be copied when an object is
     created using another object as a template.
+  - **limit**: For control types which use a tokenizer control to let the user
+    select a list of values, this limits how many values can be selected. For
+    example, a "users" field with a limit of "1" will behave like the "Owner"
+    field in Maniphest and only allow selection of a single user.
 
 The `strings` value supports different strings per control type. They are: