diff --git a/zerver/lib/bugdown/api_return_values_table_generator.py b/zerver/lib/bugdown/api_return_values_table_generator.py
index 1f3817a119..e57f77c29b 100644
--- a/zerver/lib/bugdown/api_return_values_table_generator.py
+++ b/zerver/lib/bugdown/api_return_values_table_generator.py
@@ -67,8 +67,9 @@ class APIReturnValuesTablePreprocessor(Preprocessor):
             if 'additionalProperties' in return_values[return_value]:
                 ans.append(self.render_desc(return_values[return_value]['additionalProperties']
                                             ['description'], spacing + 4))
-                ans += self.render_table(return_values[return_value]['additionalProperties']['properties'],
-                                         spacing + 8)
+                if 'properties' in return_values[return_value]['additionalProperties']:
+                    ans += self.render_table(return_values[return_value]['additionalProperties']
+                                             ['properties'], spacing + 8)
             if ('items' in return_values[return_value] and
                'properties' in return_values[return_value]['items']):
                 ans += self.render_table(return_values[return_value]['items']['properties'], spacing + 4)
diff --git a/zerver/openapi/openapi.py b/zerver/openapi/openapi.py
index 6641aea0c0..3e119bdf12 100644
--- a/zerver/openapi/openapi.py
+++ b/zerver/openapi/openapi.py
@@ -141,6 +141,12 @@ def validate_array(content: List[Any], schema: Dict[str, Any]) -> None:
         # and arrays.
         if 'properties' in schema['items']:
             validate_object(item, schema['items'])
+            continue
+        # If the object was not an opaque object then
+        # the continue statement above should have
+        # been executed.
+        if 'object' in valid_types:
+            raise SchemaError('Opaque object in array')
         if 'items' in schema['items']:
             validate_array(item, schema['items'])
 
@@ -169,8 +175,17 @@ def validate_object(content: Dict[str, Any], schema: Dict[str, Any]) -> None:
             continue
         if 'additionalProperties' in schema['properties'][key]:
             for child_keys in value:
+                if type(value[child_keys]) is list:
+                    validate_array(value[child_keys],
+                                   schema['properties'][key]['additionalProperties'])
+                    continue
                 validate_object(value[child_keys],
                                 schema['properties'][key]['additionalProperties'])
+            continue
+        # If the object is not opaque then continue statements
+        # will be executed above and this will be skipped
+        if expected_type is dict:
+            raise SchemaError('Opaque object "{}"'.format(key))
     # Check that at least all the required keys are present
     if 'required' in schema:
         for req_key in schema['required']:
diff --git a/zerver/openapi/zulip.yaml b/zerver/openapi/zulip.yaml
index 3ebd6716a5..22d080cd51 100644
--- a/zerver/openapi/zulip.yaml
+++ b/zerver/openapi/zulip.yaml
@@ -1873,13 +1873,7 @@ paths:
                         The user's ID.
                       example: 1
                     profile_data:
-                      type: object
-                      description: |
-                        A dictionary containing custom profile field data for the user. Each entry
-                        maps the integer ID of a custom profile field in the organization to a
-                        dictionary containing the user's data for that field.  Generally the data
-                        includes just a single `value` key; for those custom profile fields
-                        supporting markdown, a `rendered_value` key will also be present.
+                      $ref: '#/components/schemas/profile_data'
                 - example:
                     {
                         "avatar_url": "https://secure.gravatar.com/avatar/af4f06322c177ef4e1e9b2c424986b54?d=identicon&version=1",
@@ -3090,25 +3084,91 @@ paths:
                       description: |
                         Each key-value pair in the object indicates whether the authentication
                         method is enabled on this server.
+
+                        **Changes**: Deprecated in Zulip 2.1, in favor of the more expressive
+                        `external_authentication_methods`.
+                      properties:
+                        password:
+                          description: |
+                            Whether the user can authenticate using password.
+                          type: boolean
+                        dev:
+                          description: |
+                            Whether the user can authenticate using development api key.
+                          type: boolean
+                        email:
+                          description: |
+                            Whether the user can authenticate using email.
+                          type: boolean
+                        ldap:
+                          description: |
+                            Whether the user can authenticate using ldap.
+                          type: boolean
+                        remoteuser:
+                          description: |
+                            Whether the user can authenticate using remoteuser.
+                          type: boolean
+                        github:
+                          description: |
+                            Whether the user can authenticate using their github account.
+                          type: boolean
+                        azuread:
+                          description: |
+                            Whether the user can authenticate using their azuread account.
+                          type: boolean
+                        gitlab:
+                          description: |
+                            Whether the user can authenticate using their gitlab account.
+                          type: boolean
+                        google:
+                          description: |
+                            Whether the user can authenticate using their google account.
+                          type: boolean
+                        saml:
+                          description: |
+                            Whether the user can authenticate using saml.
+                          type: boolean
                     external_authentication_methods:
                       type: array
                       description: |
                         A list of dictionaries describing the available external
                         authentication methods (E.g. Google, GitHub, or SAML)
-                        enabled for this organization. Each dictionary specifies
-                        the name and icon that should be displayed on the login
-                        buttons (`display_name` and `display_icon`, where
-                        `display_icon` can be `null`, if no icon is to be
-                        displayed), the URLs that should be accessed to initiate
-                        login/signup using the method (`login_url` and
-                        `signup_url`) and `name`, which is a unique, stable,
-                        machine-readable name for the authentication method.
+                        enabled for this organization.
+
                         The list is sorted in the order in which these
                         authentication methods should be displayed.
 
                         **Changes**: New in Zulip 2.1.
                       items:
                         type: object
+                        properties:
+                          name:
+                            type: string
+                            description: |
+                              A unique, table, machine-readable name for the authentication method,
+                              intended to be used by clients with special behavior for specific
+                              authenatication methods to correctly identify the method.
+                          display_name:
+                            type: string
+                            description: |
+                              Display name of the authentication method, to be used in all buttons
+                              for the authentication method.
+                          display_icon:
+                            type: string
+                            nullable: true
+                            description: |
+                              URL for an image to be displayed as an icon in all buttons for
+                              the external authentication method.
+
+                              When null, no icon should be displayed.
+                          login_url:
+                            type: string
+                            description: |
+                              URL to be used to initiate authentication using this method.
+                          signup_url:
+                            type: string
+                            description: |
+                              URL to be used to initiate account registration using this method.
                     zulip_version:
                       type: string
                       description: |
@@ -4215,10 +4275,34 @@ components:
           description: |
             The time the user account was created.
         profile_data:
-          type: object
-          description: |
-            Object containing data on the user's personal values for the organization's
-            configured custom profile fields.
+          $ref: '#/components/schemas/profile_data'
+    profile_data:
+      type: object
+      description: |
+        A dictionary containing custom profile field data for the user. Each entry
+        maps the integer ID of a custom profile field in the organization to a
+        dictionary containing the user's data for that field.  Generally the data
+        includes just a single `value` key; for those custom profile fields
+        supporting markdown, a `rendered_value` key will also be present.
+      additionalProperties:
+        type: object
+        description: |
+          '{id}': Object with data about what value user filled in the custom
+                      profile field with id `id`.
+        properties:
+          value:
+            type: string
+            description: |
+              User's personal value for this custom profile field.
+          rendered_value:
+            type: string
+            description: |
+              The `value` rendered in HTML.  Will only be present for
+              custom profile field types that support markdown rendering.
+
+              This user-generated HTML content should be rendered
+              using the same CSS and client-side security protections
+              as are used for message content.
     JsonResponse:
       type: object
       properties:
@@ -4337,12 +4421,26 @@ components:
               A dictionary where the key is the email address of the user/bot and the
               value is a list of the names of the streams that were subscribed to as a
               result of the query.
+            additionalProperties:
+              description: |
+                `{email_address}`: List of the names of the streams that were subscribed
+                 to as a result of the query.
+              type: array
+              items:
+                type: string
           already_subscribed:
             type: object
             description: |
               A dictionary where the key is the email address of the user/bot and the
               value is a list of the names of the streams that the user/bot is already
               subscribed to.
+            additionalProperties:
+              description: |
+                {email_address}`: List of the names of the streams that the user is
+                already subscribed to.
+              type: array
+              items:
+                type: string
           unauthorized:
             type: array
             items: