diff --git a/modules/ppcp-api-client/src/Endpoint/BillingPlans.php b/modules/ppcp-api-client/src/Endpoint/BillingPlans.php
index 3210b0d19..df7c9eb37 100644
--- a/modules/ppcp-api-client/src/Endpoint/BillingPlans.php
+++ b/modules/ppcp-api-client/src/Endpoint/BillingPlans.php
@@ -40,16 +40,22 @@ class BillingPlans {
 	private $bearer;
 
 	/**
+	 * Billing cycle factory
+	 *
 	 * @var BillingCycleFactory
 	 */
 	private $billing_cycle_factory;
 
 	/**
+	 * Plan factory
+	 *
 	 * @var PlanFactory
 	 */
 	private $plan_factory;
 
 	/**
+	 * The logger.
+	 *
 	 * The logger.
 	 *
 	 * @var LoggerInterface
@@ -59,9 +65,11 @@ class BillingPlans {
 	/**
 	 * BillingPlans constructor.
 	 *
-	 * @param string          $host The host.
-	 * @param Bearer          $bearer The bearer.
-	 * @param LoggerInterface $logger The logger.
+	 * @param string              $host The host.
+	 * @param Bearer              $bearer The bearer.
+	 * @param BillingCycleFactory $billing_cycle_factory Billing cycle factory.
+	 * @param PlanFactory         $plan_factory Plan factory.
+	 * @param LoggerInterface     $logger The logger.
 	 */
 	public function __construct(
 		string $host,
@@ -80,7 +88,10 @@ class BillingPlans {
 	/**
 	 * Creates a subscription plan.
 	 *
-	 * @param string $product_id The product id.
+	 * @param string $name Product name.
+	 * @param string $product_id Product ID.
+	 * @param array  $billing_cycles Billing cycles.
+	 * @param array  $payment_preferences Payment preferences.
 	 *
 	 * @return Plan
 	 *
@@ -131,6 +142,16 @@ class BillingPlans {
 		return $this->plan_factory->from_paypal_response( $json );
 	}
 
+	/**
+	 * Returns a plan,
+	 *
+	 * @param string $id Plan ID.
+	 *
+	 * @return Plan
+	 *
+	 * @throws RuntimeException If the request fails.
+	 * @throws PayPalApiException If the request fails.
+	 */
 	public function plan( string $id ): Plan {
 		$bearer = $this->bearer->bearer();
 		$url    = trailingslashit( $this->host ) . 'v1/billing/plans/' . $id;
@@ -159,6 +180,17 @@ class BillingPlans {
 		return $this->plan_factory->from_paypal_response( $json );
 	}
 
+	/**
+	 * Updates pricing.
+	 *
+	 * @param string       $id Plan ID.
+	 * @param BillingCycle $billing_cycle Billing cycle.
+	 *
+	 * @return void
+	 *
+	 * @throws RuntimeException If the request fails.
+	 * @throws PayPalApiException If the request fails.
+	 */
 	public function update_pricing( string $id, BillingCycle $billing_cycle ): void {
 		$data = array(
 			'pricing_schemes' => array(
diff --git a/modules/ppcp-api-client/src/Endpoint/BillingSubscriptions.php b/modules/ppcp-api-client/src/Endpoint/BillingSubscriptions.php
index c7f910858..3145ffc7d 100644
--- a/modules/ppcp-api-client/src/Endpoint/BillingSubscriptions.php
+++ b/modules/ppcp-api-client/src/Endpoint/BillingSubscriptions.php
@@ -140,7 +140,11 @@ class BillingSubscriptions {
 	 * Cancels a Subscription.
 	 *
 	 * @param string $id Subscription ID.
+	 *
 	 * @return void
+	 *
+	 * @throws RuntimeException If the request fails.
+	 * @throws PayPalApiException If the request fails.
 	 */
 	public function cancel( string $id ): void {
 		$data = array(
@@ -177,7 +181,11 @@ class BillingSubscriptions {
 	 * Returns a Subscription object from the given ID.
 	 *
 	 * @param string $id Subscription ID.
+	 *
 	 * @return stdClass
+	 *
+	 * @throws RuntimeException If the request fails.
+	 * @throws PayPalApiException If the request fails.
 	 */
 	public function subscription( string $id ): stdClass {
 		$bearer = $this->bearer->bearer();
diff --git a/modules/ppcp-api-client/src/Endpoint/CatalogProducts.php b/modules/ppcp-api-client/src/Endpoint/CatalogProducts.php
index 6d276bc3d..32296f4ee 100644
--- a/modules/ppcp-api-client/src/Endpoint/CatalogProducts.php
+++ b/modules/ppcp-api-client/src/Endpoint/CatalogProducts.php
@@ -42,7 +42,10 @@ class CatalogProducts {
 	 * @var LoggerInterface
 	 */
 	private $logger;
+
 	/**
+	 * Product factory.
+	 *
 	 * @var ProductFactory
 	 */
 	private $product_factory;
@@ -52,6 +55,7 @@ class CatalogProducts {
 	 *
 	 * @param string          $host The host.
 	 * @param Bearer          $bearer The bearer.
+	 * @param ProductFactory  $product_factory Product factory.
 	 * @param LoggerInterface $logger The logger.
 	 */
 	public function __construct(
@@ -121,7 +125,11 @@ class CatalogProducts {
 	 *
 	 * @param string $id Product ID.
 	 * @param array  $data Data to update.
+	 *
 	 * @return void
+	 *
+	 * @throws RuntimeException If the request fails.
+	 * @throws PayPalApiException If the request fails.
 	 */
 	public function update( string $id, array $data ): void {
 		$bearer = $this->bearer->bearer();
@@ -155,7 +163,11 @@ class CatalogProducts {
 	 * Return a Product from the given ID.
 	 *
 	 * @param string $id Product ID.
+	 *
 	 * @return Product
+	 *
+	 * @throws RuntimeException If the request fails.
+	 * @throws PayPalApiException If the request fails.
 	 */
 	public function product( string $id ): Product {
 		$bearer = $this->bearer->bearer();
diff --git a/modules/ppcp-api-client/src/Entity/BillingCycle.php b/modules/ppcp-api-client/src/Entity/BillingCycle.php
index 7e8253be9..76f1c25fa 100644
--- a/modules/ppcp-api-client/src/Entity/BillingCycle.php
+++ b/modules/ppcp-api-client/src/Entity/BillingCycle.php
@@ -9,33 +9,55 @@ declare(strict_types=1);
 
 namespace WooCommerce\PayPalCommerce\ApiClient\Entity;
 
+/**
+ * Class BillingCycle
+ */
 class BillingCycle {
 
 	/**
+	 * Frequency.
+	 *
 	 * @var array
 	 */
 	private $frequency;
 
 	/**
+	 * Sequence.
+	 *
 	 * @var int
 	 */
 	private $sequence;
 
 	/**
+	 * Tenure Type.
+	 *
 	 * @var string
 	 */
 	private $tenure_type;
 
 	/**
+	 * Pricing scheme.
+	 *
 	 * @var array
 	 */
 	private $pricing_scheme;
 
 	/**
+	 * Total cycles.
+	 *
 	 * @var int
 	 */
 	private $total_cycles;
 
+	/**
+	 * BillingCycle constructor.
+	 *
+	 * @param array  $frequency Frequency.
+	 * @param int    $sequence Sequence.
+	 * @param string $tenure_type Tenure type.
+	 * @param array  $pricing_scheme Pricing scheme.
+	 * @param int    $total_cycles Total cycles.
+	 */
 	public function __construct(
 		array $frequency,
 		int $sequence,
@@ -51,6 +73,8 @@ class BillingCycle {
 	}
 
 	/**
+	 * Returns frequency.
+	 *
 	 * @return array
 	 */
 	public function frequency(): array {
@@ -58,6 +82,8 @@ class BillingCycle {
 	}
 
 	/**
+	 * Returns sequence.
+	 *
 	 * @return int
 	 */
 	public function sequence(): int {
@@ -65,6 +91,8 @@ class BillingCycle {
 	}
 
 	/**
+	 * Returns tenure type.
+	 *
 	 * @return string
 	 */
 	public function tenure_type(): string {
@@ -72,6 +100,8 @@ class BillingCycle {
 	}
 
 	/**
+	 * Returns pricing scheme.
+	 *
 	 * @return array
 	 */
 	public function pricing_scheme(): array {
@@ -79,6 +109,8 @@ class BillingCycle {
 	}
 
 	/**
+	 * Return total cycles.
+	 *
 	 * @return int
 	 */
 	public function total_cycles(): int {
diff --git a/modules/ppcp-api-client/src/Entity/PaymentPreferences.php b/modules/ppcp-api-client/src/Entity/PaymentPreferences.php
index 41b6b335c..b257c2389 100644
--- a/modules/ppcp-api-client/src/Entity/PaymentPreferences.php
+++ b/modules/ppcp-api-client/src/Entity/PaymentPreferences.php
@@ -9,27 +9,47 @@ declare(strict_types=1);
 
 namespace WooCommerce\PayPalCommerce\ApiClient\Entity;
 
+/**
+ * Class PaymentPreferences
+ */
 class PaymentPreferences {
+
 	/**
+	 * Setup fee.
+	 *
 	 * @var array
 	 */
 	private $setup_fee;
 
 	/**
+	 * Auto bill outstanding.
+	 *
 	 * @var bool
 	 */
 	private $auto_bill_outstanding;
 
 	/**
+	 * Setup fee failure action.
+	 *
 	 * @var string
 	 */
 	private $setup_fee_failure_action;
 
 	/**
+	 * Payment failure threshold.
+	 *
 	 * @var int
 	 */
 	private $payment_failure_threshold;
 
+	/**
+	 * PaymentPreferences constructor.
+	 *
+	 * @param array  $setup_fee Setup fee.
+	 * @param bool   $auto_bill_outstanding Auto bill outstanding.
+	 * @param string $setup_fee_failure_action Setup fee failure action.
+	 * @param int    $payment_failure_threshold payment failure threshold.
+	 */
 	public function __construct(
 		array $setup_fee,
 		bool $auto_bill_outstanding = true,
@@ -44,6 +64,8 @@ class PaymentPreferences {
 	}
 
 	/**
+	 * Setup fee.
+	 *
 	 * @return array
 	 */
 	public function setup_fee(): array {
@@ -51,6 +73,8 @@ class PaymentPreferences {
 	}
 
 	/**
+	 * Auto bill outstanding.
+	 *
 	 * @return bool
 	 */
 	public function auto_bill_outstanding(): bool {
@@ -58,6 +82,8 @@ class PaymentPreferences {
 	}
 
 	/**
+	 * Setup fee failure action.
+	 *
 	 * @return string
 	 */
 	public function setup_fee_failure_action(): string {
@@ -65,12 +91,19 @@ class PaymentPreferences {
 	}
 
 	/**
+	 * Payment failure threshold.
+	 *
 	 * @return int
 	 */
 	public function payment_failure_threshold(): int {
 		return $this->payment_failure_threshold;
 	}
 
+	/**
+	 * Returns Payment Preferences as array.
+	 *
+	 * @return array
+	 */
 	public function to_array():array {
 		return array(
 			'setup_fee'                 => $this->setup_fee(),
diff --git a/modules/ppcp-api-client/src/Entity/Plan.php b/modules/ppcp-api-client/src/Entity/Plan.php
index a04f99c5a..06747776b 100644
--- a/modules/ppcp-api-client/src/Entity/Plan.php
+++ b/modules/ppcp-api-client/src/Entity/Plan.php
@@ -9,38 +9,63 @@ declare(strict_types=1);
 
 namespace WooCommerce\PayPalCommerce\ApiClient\Entity;
 
+/**
+ * Class Plan
+ */
 class Plan {
 
 	/**
+	 * Plan ID.
+	 *
 	 * @var string
 	 */
 	private $id;
 
 	/**
+	 * Plan name.
+	 *
 	 * @var string
 	 */
 	private $name;
 
 	/**
+	 * Product ID.
+	 *
 	 * @var string
 	 */
 	private $product_id;
 
 	/**
+	 * Billing cycles.
+	 *
 	 * @var array
 	 */
 	private $billing_cycles;
 
 	/**
+	 * Payment preferences.
+	 *
 	 * @var PaymentPreferences
 	 */
 	private $payment_preferences;
 
 	/**
+	 * Plan status.
+	 *
 	 * @var string
 	 */
 	private $status;
 
+	/**
+	 * Plan constructor.
+	 *
+	 * @param string             $id Plan ID.
+	 * @param string             $name Plan name.
+	 * @param string             $product_id Product ID.
+	 * @param array              $billing_cycles Billing cycles.
+	 * @param PaymentPreferences $payment_preferences Payment preferences.
+	 * @param string             $status Plan status.
+	 */
 	public function __construct(
 		string $id,
 		string $name,
@@ -58,6 +83,8 @@ class Plan {
 	}
 
 	/**
+	 * Returns Plan ID.
+	 *
 	 * @return string
 	 */
 	public function id(): string {
@@ -65,6 +92,8 @@ class Plan {
 	}
 
 	/**
+	 * Returns Plan name.
+	 *
 	 * @return string
 	 */
 	public function name(): string {
@@ -72,6 +101,8 @@ class Plan {
 	}
 
 	/**
+	 * Returns Product ID.
+	 *
 	 * @return string
 	 */
 	public function product_id(): string {
@@ -79,6 +110,8 @@ class Plan {
 	}
 
 	/**
+	 * Returns Billing cycles.
+	 *
 	 * @return array
 	 */
 	public function billing_cycles(): array {
@@ -86,6 +119,8 @@ class Plan {
 	}
 
 	/**
+	 * Returns Payment preferences.
+	 *
 	 * @return PaymentPreferences
 	 */
 	public function payment_preferences(): PaymentPreferences {
@@ -93,12 +128,19 @@ class Plan {
 	}
 
 	/**
+	 * Returns Plan status.
+	 *
 	 * @return string
 	 */
 	public function status(): string {
 		return $this->status;
 	}
 
+	/**
+	 * Returns Plan as array.
+	 *
+	 * @return array
+	 */
 	public function to_array():array {
 		return array(
 			'id'                  => $this->id(),
diff --git a/modules/ppcp-api-client/src/Entity/Product.php b/modules/ppcp-api-client/src/Entity/Product.php
index f1ea29f58..63acecc80 100644
--- a/modules/ppcp-api-client/src/Entity/Product.php
+++ b/modules/ppcp-api-client/src/Entity/Product.php
@@ -9,6 +9,9 @@ declare(strict_types=1);
 
 namespace WooCommerce\PayPalCommerce\ApiClient\Entity;
 
+/**
+ * Class Product
+ */
 class Product {
 
 	/**
@@ -33,6 +36,8 @@ class Product {
 	private $description;
 
 	/**
+	 * Product constructor.
+	 *
 	 * @param string $id Product ID.
 	 * @param string $name Product name.
 	 * @param string $description Product description.
diff --git a/modules/ppcp-api-client/src/Factory/BillingCycleFactory.php b/modules/ppcp-api-client/src/Factory/BillingCycleFactory.php
index e028b9a9f..6b00ff0ac 100644
--- a/modules/ppcp-api-client/src/Factory/BillingCycleFactory.php
+++ b/modules/ppcp-api-client/src/Factory/BillingCycleFactory.php
@@ -13,6 +13,9 @@ use stdClass;
 use WC_Product;
 use WooCommerce\PayPalCommerce\ApiClient\Entity\BillingCycle;
 
+/**
+ * Class BillingCycleFactory
+ */
 class BillingCycleFactory {
 
 	/**
@@ -23,9 +26,9 @@ class BillingCycleFactory {
 	private $currency;
 
 	/**
-	 * The currency.
+	 * BillingCycleFactory constructor.
 	 *
-	 * @param string $currency
+	 * @param string $currency The currency.
 	 */
 	public function __construct( string $currency ) {
 		$this->currency = $currency;
diff --git a/modules/ppcp-api-client/src/Factory/PaymentPreferencesFactory.php b/modules/ppcp-api-client/src/Factory/PaymentPreferencesFactory.php
index ee715199c..44c0d0cef 100644
--- a/modules/ppcp-api-client/src/Factory/PaymentPreferencesFactory.php
+++ b/modules/ppcp-api-client/src/Factory/PaymentPreferencesFactory.php
@@ -13,6 +13,9 @@ use stdClass;
 use WC_Product;
 use WooCommerce\PayPalCommerce\ApiClient\Entity\PaymentPreferences;
 
+/**
+ * Class PaymentPreferencesFactory
+ */
 class PaymentPreferencesFactory {
 
 	/**
diff --git a/modules/ppcp-api-client/src/Factory/PlanFactory.php b/modules/ppcp-api-client/src/Factory/PlanFactory.php
index c51104bac..bbf332d10 100644
--- a/modules/ppcp-api-client/src/Factory/PlanFactory.php
+++ b/modules/ppcp-api-client/src/Factory/PlanFactory.php
@@ -1,4 +1,11 @@
 <?php
+/**
+ * Plan Factory.
+ *
+ * @package WooCommerce\PayPalCommerce\Webhooks\Handler
+ */
+
+declare(strict_types=1);
 
 namespace WooCommerce\PayPalCommerce\ApiClient\Factory;
 
@@ -6,17 +13,31 @@ use stdClass;
 use WooCommerce\PayPalCommerce\ApiClient\Entity\Plan;
 use WooCommerce\PayPalCommerce\ApiClient\Exception\RuntimeException;
 
+/**
+ * Class PlanFactory
+ */
 class PlanFactory {
 
 	/**
+	 * Billing cycle factory.
+	 *
 	 * @var BillingCycleFactory
 	 */
 	private $billing_cycle_factory;
+
 	/**
+	 * Payment preferences factory.
+	 *
 	 * @var PaymentPreferencesFactory
 	 */
 	private $payment_preferences_factory;
 
+	/**
+	 * PlanFactory constructor.
+	 *
+	 * @param BillingCycleFactory       $billing_cycle_factory Billing cycle factory.
+	 * @param PaymentPreferencesFactory $payment_preferences_factory Payment preferences factory.
+	 */
 	public function __construct(
 		BillingCycleFactory $billing_cycle_factory,
 		PaymentPreferencesFactory $payment_preferences_factory
@@ -25,6 +46,15 @@ class PlanFactory {
 		$this->payment_preferences_factory = $payment_preferences_factory;
 	}
 
+	/**
+	 * Returns a Plan from PayPal response.
+	 *
+	 * @param stdClass $data The data.
+	 *
+	 * @return Plan
+	 *
+	 * @throws RuntimeException If it could not create Plan.
+	 */
 	public function from_paypal_response( stdClass $data ): Plan {
 		if ( ! isset( $data->id ) ) {
 			throw new RuntimeException(
diff --git a/modules/ppcp-api-client/src/Factory/ProductFactory.php b/modules/ppcp-api-client/src/Factory/ProductFactory.php
index bd58a0e0c..a34602a21 100644
--- a/modules/ppcp-api-client/src/Factory/ProductFactory.php
+++ b/modules/ppcp-api-client/src/Factory/ProductFactory.php
@@ -13,6 +13,9 @@ use stdClass;
 use WooCommerce\PayPalCommerce\ApiClient\Entity\Product;
 use WooCommerce\PayPalCommerce\ApiClient\Exception\RuntimeException;
 
+/**
+ * Class ProductFactory
+ */
 class ProductFactory {
 
 	/**
diff --git a/modules/ppcp-button/src/Assets/SmartButton.php b/modules/ppcp-button/src/Assets/SmartButton.php
index ec6aced40..bd890c3c5 100644
--- a/modules/ppcp-button/src/Assets/SmartButton.php
+++ b/modules/ppcp-button/src/Assets/SmartButton.php
@@ -200,7 +200,10 @@ class SmartButton implements SmartButtonInterface {
 	 * @var LoggerInterface
 	 */
 	private $logger;
+
 	/**
+	 * Session handler.
+	 *
 	 * @var SessionHandler
 	 */
 	private $session_handler;
@@ -209,7 +212,8 @@ class SmartButton implements SmartButtonInterface {
 	 * SmartButton constructor.
 	 *
 	 * @param string                 $module_url The URL to the module.
-	 * @param string                 $version                            The assets version.
+	 * @param string                 $version The assets version.
+	 * @param SessionHandler         $session_handler The Session handler.
 	 * @param Settings               $settings The Settings.
 	 * @param PayerFactory           $payer_factory The Payer factory.
 	 * @param string                 $client_id The client ID.
diff --git a/modules/ppcp-wc-gateway/src/Gateway/PayPalGateway.php b/modules/ppcp-wc-gateway/src/Gateway/PayPalGateway.php
index 6cccf027c..c1aadef01 100644
--- a/modules/ppcp-wc-gateway/src/Gateway/PayPalGateway.php
+++ b/modules/ppcp-wc-gateway/src/Gateway/PayPalGateway.php
@@ -164,20 +164,21 @@ class PayPalGateway extends \WC_Payment_Gateway {
 	/**
 	 * PayPalGateway constructor.
 	 *
-	 * @param SettingsRenderer       $settings_renderer The Settings Renderer.
-	 * @param FundingSourceRenderer  $funding_source_renderer The funding source renderer.
-	 * @param OrderProcessor         $order_processor The Order Processor.
-	 * @param ContainerInterface     $config The settings.
-	 * @param SessionHandler         $session_handler The Session Handler.
-	 * @param RefundProcessor        $refund_processor The Refund Processor.
-	 * @param State                  $state The state.
+	 * @param SettingsRenderer $settings_renderer The Settings Renderer.
+	 * @param FundingSourceRenderer $funding_source_renderer The funding source renderer.
+	 * @param OrderProcessor $order_processor The Order Processor.
+	 * @param ContainerInterface $config The settings.
+	 * @param SessionHandler $session_handler The Session Handler.
+	 * @param RefundProcessor $refund_processor The Refund Processor.
+	 * @param State $state The state.
 	 * @param TransactionUrlProvider $transaction_url_provider Service providing transaction view URL based on order.
-	 * @param SubscriptionHelper     $subscription_helper The subscription helper.
-	 * @param string                 $page_id ID of the current PPCP gateway settings page, or empty if it is not such page.
-	 * @param Environment            $environment The environment.
+	 * @param SubscriptionHelper $subscription_helper The subscription helper.
+	 * @param string $page_id ID of the current PPCP gateway settings page, or empty if it is not such page.
+	 * @param Environment $environment The environment.
 	 * @param PaymentTokenRepository $payment_token_repository The payment token repository.
-	 * @param string                 $api_shop_country The api shop country.
-	 * @param LoggerInterface        $logger  The logger.
+	 * @param LoggerInterface $logger The logger.
+	 * @param string $api_shop_country The api shop country.
+	 * @param OrderEndpoint $order_endpoint The order endpoint.
 	 */
 	public function __construct(
 		SettingsRenderer $settings_renderer,