diff --git a/Gemfile b/Gemfile
index d8786e9..1ad879f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -24,4 +24,6 @@ end
 group :development, :test do
   # https://github.com/pry/pry
   gem 'pry'
+  # https://github.com/lsegal/yard
+  gem 'yard'
 end
diff --git a/lib/ngrokapi.rb b/lib/ngrokapi.rb
index d634f51..20fcfc9 100644
--- a/lib/ngrokapi.rb
+++ b/lib/ngrokapi.rb
@@ -7,5 +7,7 @@ Dir[File.join('.', 'lib', '**/*.rb')].each do |f|
   require f
 end
 
+##
+# The Module which contains the Ngrok API gem
 module NgrokAPI
 end
diff --git a/lib/ngrokapi/client.rb b/lib/ngrokapi/client.rb
index 54c26e2..10cbd84 100644
--- a/lib/ngrokapi/client.rb
+++ b/lib/ngrokapi/client.rb
@@ -1,6 +1,9 @@
 # frozen_string_literal: true
 
 module NgrokAPI
+  ##
+  # Low-level api client for communicating with Ngrok's HTTP API.
+  # Use this object to instantiate your clients.
   class Client
     attr_reader :api_key,
       :base_url
@@ -13,28 +16,107 @@ module NgrokAPI
       @base_url = base_url
     end
 
+    ##
+    # Creates and returns an instance of a NgrokAPI::Services::ApiKeysClient
+    #
+    # @return [NgrokAPI::Services::ApiKeysClient]
     def api_keys
       @_api_keys ||= NgrokAPI::Services::ApiKeysClient.new(client: self)
     end
 
+    ##
+    # Creates and returns an instance of a NgrokAPI::Services::EndpointConfigurationsClient
+    #
+    # @return [NgrokAPI::Services::EndpointConfigurationsClient]
     def endpoint_configurations
       @_endpoint_configurations ||= NgrokAPI::Services::EndpointConfigurationsClient.new(
         client: self
       )
     end
 
-    def event_streams
-      # @_event_streams ||= NgrokAPI::Services::EventStreamsClient.new(client: self)
-    end
-
+    ##
+    # Creates and returns an instance of a NgrokAPI::Services::ReservedDomainsClient
+    #
+    # @return [NgrokAPI::Services::ReservedDomainsClient]
     def reserved_domains
       @_reserved_domains ||= NgrokAPI::Services::ReservedDomainsClient.new(client: self)
     end
 
+    ##
+    # Creates and returns an instance of a NgrokAPI::Services::TlsCertificatesClient
+    #
+    # @return [NgrokAPI::Services::TlsCertificatesClient]
     def tls_certificates
       @_tls_certificates ||= NgrokAPI::Services::TlsCertificatesClient.new(client: self)
     end
 
+    ##
+    # Make a DELETE request to a given URI
+    #
+    # @param [string] path URL resource path
+    # @return [nil]
+    def delete(path)
+      uri = get_uri(path)
+      req = Net::HTTP::Delete.new(uri, headers)
+      json_do(uri, req)
+    end
+
+    ##
+    # Make a GET request to a given URI with optional data
+    #
+    # @param [string] path URL resource path
+    # @param [hash] data hash which will be converted to query parameters or form data
+    # @return [json] response body
+    def get(path, data: {})
+      uri = get_uri(path, data: data)
+      req = Net::HTTP::Get.new(uri, headers)
+      json_do(uri, req)
+    end
+
+    ##
+    # Make a GET request
+    #
+    # @param [string] before_id URL resource path
+    # @param [integer] limit URL resource path
+    # @param [string] path resource path, mutually exclusive with url
+    # @param [string] url Full URL of the resource, mutually exclusive with path
+    # @return [json] response body
+    def list(before_id: nil, limit: nil, path: nil, url: nil)
+      if path
+        data = {}
+        data[:before_id] = before_id if before_id
+        data[:limit] = limit if limit
+        get(path, data: data)
+      else
+        get(url)
+      end
+    end
+
+    ##
+    # Make a PATCH request to a given URI with optional data
+    #
+    # @param [string] path URL resource path
+    # @param [hash] data hash which will be converted to query parameters or form data
+    # @return [json] response body
+    def patch(path, data: {})
+      uri = get_uri(path)
+      req = Net::HTTP::Patch.new(uri, headers_with_json)
+      json_do(uri, req, data: data.to_json)
+    end
+
+    ##
+    # Make a POST request to a given URI with optional data
+    #
+    # @param [string] path URL resource path
+    # @param [hash] data hash which will be converted to query parameters or form data
+    # @return [json] response body
+    def post(path, data: {})
+      uri = get_uri(path)
+      req = Net::HTTP::Post.new(uri, headers_with_json)
+      json_do(uri, req, data: data.to_json)
+    end
+
+    private
     def headers
       {
         'Authorization': "Bearer #{@api_key}",
@@ -57,34 +139,14 @@ module NgrokAPI
       { use_ssl: uri.scheme == 'https' }
     end
 
+    def get_uri(path, data: nil)
+      data = data != nil ? "?#{URI.encode_www_form(data)}" : ""
+      uri = URI("#{url(path)}#{data}")
+    end
+
     def url(path)
       path = path.delete_prefix(@base_url)
       "#{@base_url}#{path}"
     end
-
-    def delete(path)
-      uri = URI(url(path))
-      req = Net::HTTP::Delete.new(uri, headers)
-      json_do(uri, req)
-    end
-
-    def get(path, data: {})
-      data = data != {} ? "?#{URI.encode_www_form(data)}" : ""
-      uri = URI("#{url(path)}#{data}")
-      req = Net::HTTP::Get.new(uri, headers)
-      json_do(uri, req)
-    end
-
-    def patch(path, data: {})
-      uri = URI(url(path))
-      req = Net::HTTP::Patch.new(uri, headers_with_json)
-      json_do(uri, req, data: data.to_json)
-    end
-
-    def post(path, data: {})
-      uri = URI(url(path))
-      req = Net::HTTP::Post.new(uri, headers_with_json)
-      json_do(uri, req, data: data.to_json)
-    end
   end
 end
diff --git a/lib/ngrokapi/models/api_key.rb b/lib/ngrokapi/models/api_key.rb
index 2c63dbf..68d9aa9 100644
--- a/lib/ngrokapi/models/api_key.rb
+++ b/lib/ngrokapi/models/api_key.rb
@@ -2,6 +2,8 @@
 
 module NgrokAPI
   module Models
+    ##
+    # A resource representing data from the api_keys API
     class ApiKey
       attr_reader :id,
         :client,
@@ -31,10 +33,24 @@ module NgrokAPI
       def to_s
       end
 
+      ##
+      # Delete this API key.
+      #
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-api-keys-delete
       def delete
         @client.delete(id: @id)
       end
 
+      ##
+      # Update the attributes of this API key.
+      #
+      # @param [string] description human-readable description of what uses the API key to authenticate. optional, max 255 bytes.
+      # @param [string] metadata arbitrary user-defined data of this API key. optional, max 4096 bytes
+      # @return [NgrokAPI::Models::ApiKey] result from update request
+      #
+      # https://ngrok.com/docs/api#api-api-keys-update
       def update(description: nil, metadata: nil)
         @description = description if description
         @metadata = metadata if metadata
diff --git a/lib/ngrokapi/models/api_key_list.rb b/lib/ngrokapi/models/api_key_list.rb
deleted file mode 100644
index 5cb88ad..0000000
--- a/lib/ngrokapi/models/api_key_list.rb
+++ /dev/null
@@ -1,33 +0,0 @@
-# frozen_string_literal: true
-
-module NgrokAPI
-  module Models
-    class ApiKeyList
-      attr_reader :client,
-        :keys,
-        :iter,
-        :next_page_uri,
-        :result,
-        :uri
-
-      def initialize(client:, result:)
-        @client = client
-        @result = result
-        @next_page_uri = @result['next_page_uri']
-        @uri = @result['uri']
-        @keys = @result['keys'].each do |result|
-          NgrokAPI::Models::ApiKey.new(client: client, result: result)
-        end
-        @iter = NgrokAPI::PagedIterator.new(client: client, page: self, list_property: 'keys')
-      end
-
-      # TODO: equality
-      def ==(other)
-      end
-
-      # TODO: to_s
-      def to_s
-      end
-    end
-  end
-end
diff --git a/lib/ngrokapi/models/endpoint_configuration.rb b/lib/ngrokapi/models/endpoint_configuration.rb
index 49ff80b..9ac23ba 100644
--- a/lib/ngrokapi/models/endpoint_configuration.rb
+++ b/lib/ngrokapi/models/endpoint_configuration.rb
@@ -2,6 +2,8 @@
 
 module NgrokAPI
   module Models
+    ##
+    # A resource representing data from the endpoint_configuration API
     class EndpointConfiguration
       attr_reader :id,
         :client,
@@ -29,14 +31,85 @@ module NgrokAPI
       def to_s
       end
 
+      ##
+      # Delete this endpoint configuration.
+      #
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-endpoint-configurations-delete
       def delete
         @client.delete(id: @id)
       end
 
-      def update(description: nil, metadata: nil)
+      ##
+      # Update this endpoint configuration. If a module is not specified in the update, it will not be modified.
+      # However, each module configuration that is specified will completely replace the existing value.
+      # There is no way to delete an existing module via this API, instead use the delete module API.
+      #
+      # @param [string] description human-readable description of what this endpoint configuration will be do when applied or what traffic it will be applied to. Optional, max 255 bytes
+      # @param [string] metadata arbitrary user-defined machine-readable data of this endpoint configuration. Optional, max 4096 bytes.
+      # @param [string] circuit_breaker circuit breaker module configuration
+      # @param [string] compression compression module configuration
+      # @param [string] request_headers request headers module configuration
+      # @param [string] response_headers response headers module configuration
+      # @param [string] ip_policy ip policy module configuration
+      # @param [string] mutual_tls mutual TLS module configuration
+      # @param [string] tls_termination TLS termination module configuration
+      # @param [string] webhook_validation webhook validation module configuration
+      # @param [string] oauth oauth module configuration
+      # @param [string] logging logging module configuration
+      # @param [string] saml saml module configuration
+      # @param [string] oidc oidc module configuration
+      # @return
+      #
+      # https://ngrok.com/docs/api#api-endpoint-configurations-update
+      def update(
+        description: nil,
+        metadata: nil,
+        circuit_breaker: nil,
+        compression: nil,
+        request_headers: nil,
+        response_headers: nil,
+        ip_policy: nil,
+        mutual_tls: nil,
+        tls_termination: nil,
+        webhook_validation: nil,
+        oauth: nil,
+        logging: nil,
+        saml: nil,
+        oidc: nil
+      )
         @description = description if description
         @metadata = metadata if metadata
-        @client.update(id: @id, description: description, metadata: metadata)
+        @circuit_breaker = circuit_breaker if circuit_breaker
+        @compression = compression if compression
+        @request_headers = request_headers if request_headers
+        @response_headers = response_headers if response_headers
+        @ip_policy = ip_policy if ip_policy
+        @mutual_tls = mutual_tls if mutual_tls
+        @tls_termination = tls_termination if tls_termination
+        @webhook_validation = webhook_validation if webhook_validation
+        @oauth = oauth if oauth
+        @logging = logging if logging
+        @saml = saml if saml
+        @oidc = oidc if oidc
+        @client.update(
+          id: @id,
+          description: description,
+          metadata: metadata,
+          circuit_breaker: circuit_breaker,
+          compression: compression,
+          request_headers: request_headers,
+          response_headers: response_headers,
+          ip_policy: ip_policy,
+          mutual_tls: mutual_tls,
+          tls_termination: tls_termination,
+          webhook_validation: webhook_validation,
+          oauth: oauth,
+          logging: logging,
+          saml: saml,
+          oidc: oidc
+        )
       end
     end
   end
diff --git a/lib/ngrokapi/models/listable.rb b/lib/ngrokapi/models/listable.rb
index f98b2d1..580233e 100644
--- a/lib/ngrokapi/models/listable.rb
+++ b/lib/ngrokapi/models/listable.rb
@@ -2,6 +2,8 @@
 
 module NgrokAPI
   module Models
+    ##
+    # A resource representing multiple instances from a given "list" API call
     class Listable
       attr_reader :client,
         :klass,
@@ -18,7 +20,7 @@ module NgrokAPI
         @list_property = list_property
         @next_page_uri = @result['next_page_uri']
         @uri = @result['uri']
-        @items = @result[list_property].each do |result|
+        @items = @result[list_property].map do |result|
           klass.new(client: client, result: result)
         end
         @iter = NgrokAPI::PagedIterator.new(
diff --git a/lib/ngrokapi/models/reserved_domain.rb b/lib/ngrokapi/models/reserved_domain.rb
index 62186a8..efa8c3f 100644
--- a/lib/ngrokapi/models/reserved_domain.rb
+++ b/lib/ngrokapi/models/reserved_domain.rb
@@ -2,6 +2,8 @@
 
 module NgrokAPI
   module Models
+    ##
+    # A resource representing data from the reserved_domains API
     class ReservedDomain
       attr_reader :id,
         :certificate,
@@ -45,10 +47,28 @@ module NgrokAPI
       def to_s
       end
 
+      ##
+      # Delete this reserved domain.
+      #
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-delete
       def delete
         @client.delete(id: @id)
       end
 
+      ##
+      # Update the attributes of this reserved domain.
+      #
+      # @param [string] description human-readable description of what this reserved domain will be used for
+      # @param [string] metadata arbitrary user-defined machine-readable data of this reserved domain. Optional, max 4096 bytes.
+      # @param [string] http_endpoint_configuration_id ID of an endpoint configuration of type http that will be used to handle inbound http traffic to this domain
+      # @param [string] https_endpoint_configuration_id ID of an endpoint configuration of type https that will be used to handle inbound https traffic to this domain
+      # @param [string] certificate_id ID of a user-uploaded TLS certificate to use for connections to targeting this domain. Optional, mutually exclusive with ``certificate_management_policy``.
+      # @param [string] certificate_management_policy configuration for automatic management of TLS certificates for this domain, or null if automatic management is disabled. Optional, mutually exclusive with ``certificate_id``.
+      # @return [NgrokAPI::Models::ReservedDomain] result from update request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-update
       def update(
         certificate_id: nil,
         certificate_management_policy: nil,
@@ -80,32 +100,70 @@ module NgrokAPI
         )
       end
 
-      def delete_certificate(id: nil)
+      ##
+      # Detach the certificate attached from this reserved domain.
+      #
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-delete-certificate
+      def delete_certificate
         @certificate = nil
         @client.delete_certificate(id: @id)
       end
 
-      def delete_certificate_management_policy(id: nil)
+      ##
+      # Detach the certificate management policy attached from this reserved domain.
+      #
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-delete-certificate-management-policy
+      def delete_certificate_management_policy
         @certificate_management_policy = nil
         @certificate_management_status = nil
         @client.delete_certificate_management_policy(id: @id)
       end
 
-      def delete_http_endpoint_config(id: nil)
+      ##
+      # Detach the http endpoint configuration attached from this reserved domain.
+      #
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-delete-http-endpoint-config
+      def delete_http_endpoint_config
         @http_endpoint_configuration = nil
         @client.delete_http_endpoint_config(id: @id)
       end
 
-      def delete_https_endpoint_config(id: nil)
+      ##
+      # Detach the https endpoint configuration attached from this reserved domain.
+      #
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-delete-https-endpoint-config
+      def delete_https_endpoint_config
         @https_endpoint_configuration = nil
         @client.delete_https_endpoint_config(id: @id)
       end
 
+      ##
+      # Restore the certificate attached to this reserved domain.
+      # Only works if the @result is still present from a previous action
+      #
+      # @return [NgrokAPI::Models::ReservedDomain] result from update request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-update
       def restore_certificate
         @certificate = @result['certificate']
         @client.update(id: @id, certificate_id: @result['certificate']['id'])
       end
 
+      ##
+      # Restore the certificate management policy attached to this reserved domain.
+      # Only works if the @result is still present from a previous action
+      #
+      # @return [NgrokAPI::Models::ReservedDomain] result from update request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-update
       def restore_certificate_management_policy
         @certificate_management_policy = @result['certificate_management_policy']
         @certificate_management_status = @result['certificate_management_status']
@@ -115,6 +173,13 @@ module NgrokAPI
         )
       end
 
+      ##
+      # Restore the http endpoint configuration attached to this reserved domain.
+      # Only works if the @result is still present from a previous action
+      #
+      # @return [NgrokAPI::Models::ReservedDomain] result from update request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-update
       def restore_http_endpoint_config
         @http_endpoint_configuration = @result['http_endpoint_configuration']
         @client.update(
@@ -123,6 +188,13 @@ module NgrokAPI
         )
       end
 
+      ##
+      # Restore the https endpoint configuration attached to this reserved domain.
+      # Only works if the @result is still present from a previous action
+      #
+      # @return [NgrokAPI::Models::ReservedDomain] result from update request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-update
       def restore_https_endpoint_config
         @https_endpoint_configuration = @result['https_endpoint_configuration']
         @client.update(
diff --git a/lib/ngrokapi/models/tls_certificate.rb b/lib/ngrokapi/models/tls_certificate.rb
index 174ec08..8f8cdf6 100644
--- a/lib/ngrokapi/models/tls_certificate.rb
+++ b/lib/ngrokapi/models/tls_certificate.rb
@@ -2,6 +2,8 @@
 
 module NgrokAPI
   module Models
+    ##
+    # A resource representing data from the tls_certificate API
     class TlsCertificate
       attr_reader :id,
         :client,
@@ -29,10 +31,24 @@ module NgrokAPI
       def to_s
       end
 
+      ##
+      # Delete this TLS certificate.
+      #
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-tls-certificates-delete
       def delete
         @client.delete(id: @id)
       end
 
+      ##
+      # Update the attributes of this TLS Certificate.
+      #
+      # @param [string] description human-readable description of this TLS certificate. optional, max 255 bytes.
+      # @param [string] metadata arbitrary user-defined machine-readable data of this TLS certificate. optional, max 4096 bytes.
+      # @return [NgrokAPI::Models::TlsCertificate] result from update request
+      #
+      # https://ngrok.com/docs/api#api-tls-certificates-update
       def update(description: nil, metadata: nil)
         @description = description if description
         @metadata = metadata if metadata
diff --git a/lib/ngrokapi/paged_iterator.rb b/lib/ngrokapi/paged_iterator.rb
index 73f0503..e2e63bf 100644
--- a/lib/ngrokapi/paged_iterator.rb
+++ b/lib/ngrokapi/paged_iterator.rb
@@ -1,6 +1,8 @@
 # frozen_string_literal: true
 
 module NgrokAPI
+  ##
+  # Low level class which allows the user to iterate through the results of a list API call
   class PagedIterator
     attr_accessor :page, :n
     attr_reader :client, :list_property
@@ -16,6 +18,11 @@ module NgrokAPI
       @page = page
     end
 
+    ##
+    # Iterate through the result set, returning the next instance if we already have one, or make
+    # a new API call to next_page_uri to get more results and return the next one from that call.
+    #
+    # @return [object] Returns an instance of a class.
     def get_next
       begin
         item = @page.result[@list_property][@n]
diff --git a/lib/ngrokapi/services/api_keys_client.rb b/lib/ngrokapi/services/api_keys_client.rb
index c0600c6..141c31f 100644
--- a/lib/ngrokapi/services/api_keys_client.rb
+++ b/lib/ngrokapi/services/api_keys_client.rb
@@ -2,8 +2,14 @@
 
 module NgrokAPI
   module Services
+    ##
+    # A client for interacting with the api_keys API
+    #
+    # https://ngrok.com/docs/api#api-api-keys
     class ApiKeysClient
+      # The List Property from the resulting API for list calls
       LIST_PROPERTY = 'keys'.freeze
+      # The API path for API keys
       PATH = '/api_keys'.freeze
 
       attr_reader :client
@@ -12,6 +18,14 @@ module NgrokAPI
         @client = client
       end
 
+      ##
+      # Create a new API key. The generated API key can be used to authenticate to the ngrok API.
+      #
+      # @param [string] description human-readable description of what uses the API key to authenticate. optional, max 255 bytes.
+      # @param [string] metadata arbitrary user-defined data of this API key. optional, max 4096 bytes
+      # @return [NgrokAPI::Models::ApiKey] result from create request
+      #
+      # https://ngrok.com/docs/api#api-api-keys-create
       def create(description: nil, metadata: nil)
         data = {}
         data[:description] = description if description
@@ -20,24 +34,40 @@ module NgrokAPI
         NgrokAPI::Models::ApiKey.new(client: self, result: result)
       end
 
+      ##
+      # Delete an API key by ID.
+      #
+      # @param [string] id a resource identifier
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-api-keys-delete
       def delete(id: nil)
         @client.delete("#{PATH}/#{id}")
       end
 
+      ##
+      # Get the details of an API key by ID.
+      #
+      # @param [string] id a resource identifier
+      # @return [NgrokAPI::Models::ApiKey] result from get request
+      #
+      # https://ngrok.com/docs/api#api-api-keys-get
       def get(id: nil)
         result = @client.get("#{PATH}/#{id}")
         NgrokAPI::Models::ApiKey.new(client: self, result: result)
       end
 
+      ##
+      # List all API keys owned by this account.
+      #
+      # @param [string] before_id
+      # @param [integer] limit
+      # @param [string] url optional and mutually exclusive from before_id and limit
+      # @return [NgrokAPI::Models::Listable] the result listable
+      #
+      # https://ngrok.com/docs/api#api-api-keys-list
       def list(before_id: nil, limit: nil, url: nil)
-        result = if url.nil?
-          data = {}
-          data[:before_id] = before_id if before_id
-          data[:limit] = limit if limit
-          @client.get(PATH, data: data)
-        else
-          @client.get(url)
-        end
+        result = @client.list(before_id: before_id, limit: limit, url: url, path: PATH)
         NgrokAPI::Models::Listable.new(
           client: self,
           result: result,
@@ -46,6 +76,15 @@ module NgrokAPI
         )
       end
 
+      ##
+      # Update attributes of an API key by ID.
+      #
+      # @param [string] id
+      # @param [string] description human-readable description of what uses the API key to authenticate. optional, max 255 bytes.
+      # @param [string] metadata arbitrary user-defined data of this API key. optional, max 4096 bytes
+      # @return [NgrokAPI::Models::ApiKey] result from update request
+      #
+      # https://ngrok.com/docs/api#api-api-keys-update
       def update(id: nil, description: nil, metadata: nil)
         data = {}
         data[:description] = description if description
diff --git a/lib/ngrokapi/services/endpoint_configurations_client.rb b/lib/ngrokapi/services/endpoint_configurations_client.rb
index a94d779..ac4d646 100644
--- a/lib/ngrokapi/services/endpoint_configurations_client.rb
+++ b/lib/ngrokapi/services/endpoint_configurations_client.rb
@@ -2,8 +2,14 @@
 
 module NgrokAPI
   module Services
+    ##
+    # A client for interacting with the endpoint_configuration API
+    #
+    # https://ngrok.com/docs/api#api-endpoint-configurations
     class EndpointConfigurationsClient
+      # The List Property from the resulting API for list calls
       LIST_PROPERTY = 'endpoint_configurations'.freeze
+      # The API path for endpoint configurations
       PATH = '/endpoint_configurations'.freeze
 
       attr_reader :client
@@ -12,38 +18,99 @@ module NgrokAPI
         @client = client
       end
 
+      ##
+      # Create a new endpoint configuration
+      #
+      # @param [string] description human-readable description of what this endpoint configuration will be do when applied or what traffic it will be applied to. Optional, max 255 bytes
+      # @param [string] metadata arbitrary user-defined machine-readable data of this endpoint configuration. Optional, max 4096 bytes.
+      # @param [string] type they type of traffic this endpoint configuration can be applied to. one of: ``http``, ``https``, ``tcp``
+      # @param [string] circuit_breaker circuit breaker module configuration
+      # @param [string] compression compression module configuration
+      # @param [string] request_headers request headers module configuration
+      # @param [string] response_headers response headers module configuration
+      # @param [string] ip_policy ip policy module configuration
+      # @param [string] mutual_tls mutual TLS module configuration
+      # @param [string] tls_termination TLS termination module configuration
+      # @param [string] webhook_validation webhook validation module configuration
+      # @param [string] oauth oauth module configuration
+      # @param [string] logging logging module configuration
+      # @param [string] saml saml module configuration
+      # @param [string] oidc oidc module configuration
+      # @return [NgrokAPI::Models::EndpointConfiguration] result from create request
+      #
+      # https://ngrok.com/docs/api#api-endpoint-configurations-create
       def create(
         description: '',
         metadata: '',
-        type: ''
+        type: '',
+        circuit_breaker: nil,
+        compression: nil,
+        request_headers: nil,
+        response_headers: nil,
+        ip_policy: nil,
+        mutual_tls: nil,
+        tls_termination: nil,
+        webhook_validation: nil,
+        oauth: nil,
+        logging: nil,
+        saml: nil,
+        oidc: nil
       )
         data = {
           type: type,
           description: description,
           metadata: metadata,
+          circuit_breaker: circuit_breaker,
+          compression: compression,
+          request_headers: request_headers,
+          response_headers: response_headers,
+          ip_policy: ip_policy,
+          mutual_tls: mutual_tls,
+          tls_termination: tls_termination,
+          webhook_validation: webhook_validation,
+          oauth: oauth,
+          logging: logging,
+          saml: saml,
+          oidc: oidc,
         }
         result = @client.post(PATH, data: data)
         NgrokAPI::Models::EndpointConfiguration.new(client: self, result: result)
       end
 
+      ##
+      # Delete an endpoint configuration. This operation will fail if the endpoint configuration is still referenced by any reserved domain or reserved address.
+      #
+      # @param [string] id a resource identifier
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-endpoint-configurations-delete
       def delete(id: nil)
         @client.delete("#{PATH}/#{id}")
       end
 
+      ##
+      # Returns detailed information about an endpoint configuration by ID.
+      #
+      # @param [string] id a resource identifier
+      # @return [NgrokAPI::Models::EndpointConfiguration] result from get request
+      #
+      # https://ngrok.com/docs/api#api-endpoint-configurations-get
       def get(id: nil)
         result = @client.get("#{PATH}/#{id}")
         NgrokAPI::Models::EndpointConfiguration.new(client: self, result: result)
       end
 
+      ##
+      # Returns a list of all endpoint configurations on this account.
+      #
+      # @param [string] before_id
+      # @param [integer] limit
+      # @param [string] url optional and mutually exclusive from before_id and limit
+      # @return [NgrokAPI::Models::Listable] the result listable
+      #
+      # https://ngrok.com/docs/api#api-endpoint-configurations-list
       def list(before_id: nil, limit: nil, url: nil)
-        result = if url.nil?
-          data = {}
-          data[:before_id] = before_id if before_id
-          data[:limit] = limit if limit
-          @client.get(PATH, data: data)
-        else
-          @client.get(url)
-        end
+        result = @client.list(before_id: before_id, limit: limit, url: url, path: PATH)
         NgrokAPI::Models::Listable.new(
           client: self,
           result: result,
@@ -52,28 +119,61 @@ module NgrokAPI
         )
       end
 
+      ##
+      # Updates an endpoint configuration. If a module is not specified in the update, it will not be modified.
+      # However, each module configuration that is specified will completely replace the existing value.
+      # There is no way to delete an existing module via this API, instead use the delete module API.
+      #
+      # @param [string] id unique identifier of this endpoint configuration
+      # @param [string] description human-readable description of what this endpoint configuration will be do when applied or what traffic it will be applied to. Optional, max 255 bytes
+      # @param [string] metadata arbitrary user-defined machine-readable data of this endpoint configuration. Optional, max 4096 bytes.
+      # @param [string] circuit_breaker circuit breaker module configuration
+      # @param [string] compression compression module configuration
+      # @param [string] request_headers request headers module configuration
+      # @param [string] response_headers response headers module configuration
+      # @param [string] ip_policy ip policy module configuration
+      # @param [string] mutual_tls mutual TLS module configuration
+      # @param [string] tls_termination TLS termination module configuration
+      # @param [string] webhook_validation webhook validation module configuration
+      # @param [string] oauth oauth module configuration
+      # @param [string] logging logging module configuration
+      # @param [string] saml saml module configuration
+      # @param [string] oidc oidc module configuration
+      # @return [NgrokAPI::Models::EndpointConfiguration] result from update request
+      #
+      # https://ngrok.com/docs/api#api-endpoint-configurations-update
       def update(
         id: nil,
-        certificate_id: nil,
-        certificate_management_policy: nil,
         description: nil,
-        http_endpoint_configuration_id: nil,
-        https_endpoint_configuration_id: nil,
-        metadata: nil
+        metadata: nil,
+        circuit_breaker: nil,
+        compression: nil,
+        request_headers: nil,
+        response_headers: nil,
+        ip_policy: nil,
+        mutual_tls: nil,
+        tls_termination: nil,
+        webhook_validation: nil,
+        oauth: nil,
+        logging: nil,
+        saml: nil,
+        oidc: nil
       )
         data = {}
-        data[:certificate_id] = certificate_id if certificate_id
-        if certificate_management_policy
-          data[:certificate_management_policy] = certificate_management_policy
-        end
         data[:description] = description if description
-        if http_endpoint_configuration_id
-          data[:http_endpoint_configuration_id] = http_endpoint_configuration_id
-        end
-        if https_endpoint_configuration_id
-          data[:https_endpoint_configuration_id] = https_endpoint_configuration_id
-        end
         data[:metadata] = metadata if metadata
+        data[:circuit_breaker] = circuit_breaker if circuit_breaker
+        data[:compression] = compression if compression
+        data[:request_headers] = request_headers if request_headers
+        data[:response_headers] = response_headers if response_headers
+        data[:ip_policy] = ip_policy if ip_policy
+        data[:mutual_tls] = mutual_tls if mutual_tls
+        data[:tls_termination] = tls_termination if tls_termination
+        data[:webhook_validation] = webhook_validation if webhook_validation
+        data[:oauth] = oauth if oauth
+        data[:logging] = logging if logging
+        data[:saml] = saml if saml
+        data[:oidc] = oidc if oidc
         result = @client.patch("#{PATH}/#{id}", data: data)
         NgrokAPI::Models::EndpointConfiguration.new(client: self, result: result)
       end
diff --git a/lib/ngrokapi/services/reserved_domains_client.rb b/lib/ngrokapi/services/reserved_domains_client.rb
index 090e727..072dd88 100644
--- a/lib/ngrokapi/services/reserved_domains_client.rb
+++ b/lib/ngrokapi/services/reserved_domains_client.rb
@@ -2,8 +2,14 @@
 
 module NgrokAPI
   module Services
+    ##
+    # A client for interacting with the reserved_domains API
+    #
+    # https://ngrok.com/docs/api#api-reserved-domains
     class ReservedDomainsClient
+      # The List Property from the resulting API for list calls
       LIST_PROPERTY = 'reserved_domains'.freeze
+      # The API path for reserved domains
       PATH = '/reserved_domains'.freeze
 
       attr_reader :client
@@ -12,6 +18,20 @@ module NgrokAPI
         @client = client
       end
 
+      ##
+      # Create a new reserved domain.
+      #
+      # @param [string] name the domain name to reserve. It may be a full domain name like app.example.com. If the name does not contain a '.' it will reserve that subdomain on ngrok.io.
+      # @param [string] region reserve the domain in this geographic ngrok datacenter. Optional, default is us. (au, eu, ap, us, jp, in, sa)
+      # @param [string] description human-readable description of what this reserved domain will be used for
+      # @param [string] metadata arbitrary user-defined machine-readable data of this reserved domain. Optional, max 4096 bytes.
+      # @param [string] http_endpoint_configuration_id ID of an endpoint configuration of type http that will be used to handle inbound http traffic to this domain
+      # @param [string] https_endpoint_configuration_id ID of an endpoint configuration of type https that will be used to handle inbound https traffic to this domain
+      # @param [string] certificate_id ID of a user-uploaded TLS certificate to use for connections to targeting this domain. Optional, mutually exclusive with ``certificate_management_policy``.
+      # @param [string] certificate_management_policy configuration for automatic management of TLS certificates for this domain, or null if automatic management is disabled. Optional, mutually exclusive with ``certificate_id``.
+      # @return [NgrokAPI::Models::ReservedDomain] result from create request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-create
       def create(
         name: '',
         region: '',
@@ -36,24 +56,40 @@ module NgrokAPI
         NgrokAPI::Models::ReservedDomain.new(client: self, result: result)
       end
 
+      ##
+      # Delete a reserved domain.
+      #
+      # @param [string] id a resource identifier
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-delete
       def delete(id: nil)
         @client.delete("#{PATH}/#{id}")
       end
 
+      ##
+      # Get the details of a reserved domain.
+      #
+      # @param [string] id a resource identifier
+      # @return [NgrokAPI::Models::ReservedDomain] result from get request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-get
       def get(id: nil)
         result = @client.get("#{PATH}/#{id}")
         NgrokAPI::Models::ReservedDomain.new(client: self, result: result)
       end
 
+      ##
+      # List all reserved domains on this account.
+      #
+      # @param [string] before_id
+      # @param [integer] limit
+      # @param [string] url optional and mutually exclusive from before_id and limit
+      # @return [NgrokAPI::Models::Listable] result from list request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-list
       def list(before_id: nil, limit: nil, url: nil)
-        result = if url.nil?
-          data = {}
-          data[:before_id] = before_id if before_id
-          data[:limit] = limit if limit
-          @client.get(PATH, data: data)
-        else
-          @client.get(url)
-        end
+        result = @client.list(before_id: before_id, limit: limit, url: url, path: PATH)
         NgrokAPI::Models::Listable.new(
           client: self,
           result: result,
@@ -62,6 +98,19 @@ module NgrokAPI
         )
       end
 
+      ##
+      # Update the attributes of a reserved domain.
+      #
+      # @param [string] id
+      # @param [string] description human-readable description of what this reserved domain will be used for
+      # @param [string] metadata arbitrary user-defined machine-readable data of this reserved domain. Optional, max 4096 bytes.
+      # @param [string] http_endpoint_configuration_id ID of an endpoint configuration of type http that will be used to handle inbound http traffic to this domain
+      # @param [string] https_endpoint_configuration_id ID of an endpoint configuration of type https that will be used to handle inbound https traffic to this domain
+      # @param [string] certificate_id ID of a user-uploaded TLS certificate to use for connections to targeting this domain. Optional, mutually exclusive with ``certificate_management_policy``.
+      # @param [string] certificate_management_policy configuration for automatic management of TLS certificates for this domain, or null if automatic management is disabled. Optional, mutually exclusive with ``certificate_id``.
+      # @return [NgrokAPI::Models::ReservedDomain] result from update request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-update
       def update(
         id: nil,
         certificate_id: nil,
@@ -88,18 +137,46 @@ module NgrokAPI
         NgrokAPI::Models::ReservedDomain.new(client: self, result: result)
       end
 
-      def delete_certificate_management_policy(id: nil)
-        @client.delete("#{PATH}/#{id}/certificate_management_policy")
-      end
-
+      ##
+      # Detach the certificate attached from a reserved domain.
+      #
+      # @param [string] id a resource identifier
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-delete-certificate
       def delete_certificate(id: nil)
         @client.delete("#{PATH}/#{id}/certificate")
       end
 
+      ##
+      # Detach the certificate management policy attached from a reserved domain.
+      #
+      # @param [string] id a resource identifier
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-delete-certificate-management-policy
+      def delete_certificate_management_policy(id: nil)
+        @client.delete("#{PATH}/#{id}/certificate_management_policy")
+      end
+
+      ##
+      # Detach the http endpoint configuration attached from a reserved domain.
+      #
+      # @param [string] id a resource identifier
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-delete-http-endpoint-config
       def delete_http_endpoint_config(id: nil)
         @client.delete("#{PATH}/#{id}/http_endpoint_configuration")
       end
 
+      ##
+      # Detach the https endpoint configuration attached from a reserved domain.
+      #
+      # @param [string] id a resource identifier
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-reserved-domains-delete-https-endpoint-config
       def delete_https_endpoint_config(id: nil)
         @client.delete("#{PATH}/#{id}/https_endpoint_configuration")
       end
diff --git a/lib/ngrokapi/services/tls_certificates_client.rb b/lib/ngrokapi/services/tls_certificates_client.rb
index 95fff2d..3eaaa98 100644
--- a/lib/ngrokapi/services/tls_certificates_client.rb
+++ b/lib/ngrokapi/services/tls_certificates_client.rb
@@ -2,8 +2,14 @@
 
 module NgrokAPI
   module Services
+    ##
+    # A client for interacting with the tls_certificates API
+    #
+    # https://ngrok.com/docs/api#api-tls-certificates
     class TlsCertificatesClient
+      # The List Property from the resulting API for list calls
       LIST_PROPERTY = 'tls_certificates'.freeze
+      # The API path for tls certificates
       PATH = '/tls_certificates'.freeze
 
       attr_reader :client
@@ -12,6 +18,16 @@ module NgrokAPI
         @client = client
       end
 
+      ##
+      # Upload a new TLS certificate.
+      #
+      # @param [string] description human-readable description of this TLS certificate. optional, max 255 bytes.
+      # @param [string] metadata arbitrary user-defined machine-readable data of this TLS certificate. optional, max 4096 bytes.
+      # @param [string] certificate_pem chain of PEM-encoded certificates, leaf first. See `Certificate Bundles` <https://ngrok.com/docs/api#tls-certificates-pem>`_.
+      # @param [string] private_key_pem private key for the TLS certificate, PEM-encoded. See `Private Keys` <https://ngrok.com/docs/ngrok-link#tls-certificates-key>`_.
+      # @return [NgrokAPI::Models::TlsCertificate] result from create request
+      #
+      # https://ngrok.com/docs/api#api-tls-certificates-create
       def create(
         certificate_pem: '',
         description: '',
@@ -28,24 +44,40 @@ module NgrokAPI
         NgrokAPI::Models::TlsCertificate.new(client: self, result: result)
       end
 
+      ##
+      # Delete a TLS certificate by ID.
+      #
+      # @param [string] id a resource identifier
+      # @return [nil] result from delete request
+      #
+      # https://ngrok.com/docs/api#api-tls-certificates-delete
       def delete(id: nil)
         @client.delete("#{PATH}/#{id}")
       end
 
+      ##
+      # Get detailed information about a TLS certificate by ID.
+      #
+      # @param [string] id a resource identifier
+      # @return [NgrokAPI::Models::TlsCertificate] result from get request
+      #
+      # https://ngrok.com/docs/api#api-tls-certificates-get
       def get(id: nil)
         result = @client.get("#{PATH}/#{id}")
         NgrokAPI::Models::TlsCertificate.new(client: self, result: result)
       end
 
+      ##
+      # List all TLS certificates on this account.
+      #
+      # @param [string] before_id
+      # @param [integer] limit
+      # @param [string] url optional and mutually exclusive from before_id and limit
+      # @return [NgrokAPI::Models::Listable] the result listable
+      #
+      # https://ngrok.com/docs/api#api-tls-certificates-list
       def list(before_id: nil, limit: nil, url: nil)
-        result = if url.nil?
-          data = {}
-          data[:before_id] = before_id if before_id
-          data[:limit] = limit if limit
-          @client.get(PATH, data: data)
-        else
-          @client.get(url)
-        end
+        result = @client.list(before_id: before_id, limit: limit, url: url, path: PATH)
         NgrokAPI::Models::Listable.new(
           client: self,
           result: result,
@@ -54,6 +86,15 @@ module NgrokAPI
         )
       end
 
+      ##
+      # Update attributes of a TLS Certificate by ID.
+      #
+      # @param [string] id
+      # @param [string] description human-readable description of this TLS certificate. optional, max 255 bytes.
+      # @param [string] metadata arbitrary user-defined machine-readable data of this TLS certificate. optional, max 4096 bytes.
+      # @return [NgrokAPI::Models::TlsCertificate] result from update request
+      #
+      # https://ngrok.com/docs/api#api-tls-certificates-update
       def update(
         id: nil,
         description: nil,
diff --git a/lib/ngrokapi/version.rb b/lib/ngrokapi/version.rb
index e462c5b..bdbad95 100644
--- a/lib/ngrokapi/version.rb
+++ b/lib/ngrokapi/version.rb
@@ -1,3 +1,4 @@
 module NgrokAPI
+  # The current version of the gem
   VERSION = '0.0.1.pre'.freeze
 end
diff --git a/spec/ngrokapi/models/api_key_list_spec.rb b/spec/ngrokapi/models/listable_spec.rb
similarity index 78%
rename from spec/ngrokapi/models/api_key_list_spec.rb
rename to spec/ngrokapi/models/listable_spec.rb
index 2771be2..b5abe83 100644
--- a/spec/ngrokapi/models/api_key_list_spec.rb
+++ b/spec/ngrokapi/models/listable_spec.rb
@@ -1,6 +1,6 @@
 require 'spec_helper'
 
-RSpec.describe NgrokAPI::Models::ApiKeyList do
+RSpec.describe NgrokAPI::Models::Listable do
   before(:each) do
     client = class_double("ApiKeysClient")
     @result = {
@@ -33,7 +33,12 @@ RSpec.describe NgrokAPI::Models::ApiKeyList do
       "uri" => "https://api.ngrok.com/api_keys",
       "next_page_uri" => nil
     }
-    @api_keys = NgrokAPI::Models::ApiKeyList.new(client: client, result: @result)
+    @listable = NgrokAPI::Models::Listable.new(
+      client: client,
+      result: @result,
+      list_property: 'keys',
+      klass: NgrokAPI::Models::ApiKey
+    )
   end
 
   describe "#==" do
@@ -50,14 +55,13 @@ RSpec.describe NgrokAPI::Models::ApiKeyList do
 
   describe "keys" do
     it "should consistent of ApiKeys" do
-      expect(@api_keys.keys.size).to eq @result['keys'].size
-      expect(true).to eq true
+      expect(@listable.items.size).to eq @result['keys'].size
     end
   end
 
   describe "iter" do
     it "should be a PagedIterator" do
-      expect(@api_keys.iter.class).to eq NgrokAPI::PagedIterator
+      expect(@listable.iter.class).to eq NgrokAPI::PagedIterator
     end
   end
 end
diff --git a/spec/paged_iterator_spec.rb b/spec/paged_iterator_spec.rb
index dfe844b..12163f2 100644
--- a/spec/paged_iterator_spec.rb
+++ b/spec/paged_iterator_spec.rb
@@ -3,7 +3,7 @@ require 'spec_helper'
 RSpec.describe NgrokAPI::PagedIterator do
   before(:each) do
     client = class_double("ApiKeysClient")
-    page = class_double("ApiKeyList")
+    result = class_double("Listable")
     @paged_iterator = NgrokAPI::PagedIterator.new(client: client, result: result)
   end