diff --git a/includes/abstracts/abstract-wc-payment-gateway.php b/includes/abstracts/abstract-wc-payment-gateway.php
index 86435eb2b66..de501071ca1 100644
--- a/includes/abstracts/abstract-wc-payment-gateway.php
+++ b/includes/abstracts/abstract-wc-payment-gateway.php
@@ -316,7 +316,7 @@ abstract class WC_Payment_Gateway extends WC_Settings_API {
 	 * @param  int $order_id
 	 * @param  float $amount
 	 * @param  string $reason
-	 * @return bool|WP_Error True or false based on success, or a WP_Error object.
+	 * @return boolean True or false based on success, or a WP_Error object.
 	 */
 	public function process_refund( $order_id, $amount = null, $reason = '' ) {
 		return false;
diff --git a/includes/abstracts/abstract-wc-payment-token.php b/includes/abstracts/abstract-wc-payment-token.php
index 4b542f95ff0..2389e2f5d9e 100644
--- a/includes/abstracts/abstract-wc-payment-token.php
+++ b/includes/abstracts/abstract-wc-payment-token.php
@@ -66,7 +66,7 @@ if ( ! defined( 'ABSPATH' ) ) {
 	/**
 	 * Returns the payment token ID.
 	 * @since 2.6.0
-	 * @return ID Token ID
+	 * @return integer Token ID
 	 */
 	public function get_id() {
 		return absint( $this->_data['id'] );
@@ -198,7 +198,7 @@ if ( ! defined( 'ABSPATH' ) ) {
 	/**
 	 * Update a payment token.
 	 * @since 2.6.0
-	 * @return True on success, false if validation failed and a payment token could not be updated
+	 * @return boolean on success, false if validation failed and a payment token could not be updated
 	 */
 	public function update() {
 		if ( false === $this->validate() ) {
@@ -234,7 +234,7 @@ if ( ! defined( 'ABSPATH' ) ) {
 	/**
 	 * Create a new payment token in the database.
 	 * @since 2.6.0
-	 * @return True on success, false if validation failed and a payment token could not be created
+	 * @return boolean on success, false if validation failed and a payment token could not be created
 	 */
 	public function create() {
 		if ( false === $this->validate() ) {
@@ -273,7 +273,7 @@ if ( ! defined( 'ABSPATH' ) ) {
 	/**
 	 * Saves a payment token to the database - does not require you to know if this is a new token or an update token.
 	 * @since 2.6.0
-	 * @return True on success, false if validation failed and a payment token could not be saved
+	 * @return boolean on success, false if validation failed and a payment token could not be saved
 	 */
 	public function save() {
 		if ( $this->get_id() > 0 ) {
diff --git a/includes/abstracts/abstract-wc-settings-api.php b/includes/abstracts/abstract-wc-settings-api.php
index 7b2ed46af10..26293f5b7b5 100644
--- a/includes/abstracts/abstract-wc-settings-api.php
+++ b/includes/abstracts/abstract-wc-settings-api.php
@@ -226,7 +226,7 @@ abstract class WC_Settings_API {
 	 *
 	 * @param  string $key
 	 * @param  mixed  $empty_value
-	 * @return mixed  The value specified for the option or a default value for the option.
+	 * @return string  The value specified for the option or a default value for the option.
 	 */
 	public function get_option( $key, $empty_value = null ) {
 		if ( empty( $this->settings ) ) {
diff --git a/includes/api/class-wc-rest-product-attributes-controller.php b/includes/api/class-wc-rest-product-attributes-controller.php
index f397719adc7..685e0d9d51a 100644
--- a/includes/api/class-wc-rest-product-attributes-controller.php
+++ b/includes/api/class-wc-rest-product-attributes-controller.php
@@ -494,7 +494,6 @@ class WC_REST_Product_Attributes_Controller extends WC_REST_Controller {
 	 * Prepare links for the request.
 	 *
 	 * @param object $attribute Attribute object.
-	 * @param WP_REST_Request $request Full details about the request.
 	 * @return array Links for the given attribute.
 	 */
 	protected function prepare_links( $attribute ) {
@@ -586,7 +585,7 @@ class WC_REST_Product_Attributes_Controller extends WC_REST_Controller {
 	 * Get attribute name.
 	 *
 	 * @param WP_REST_Request $request Full details about the request.
-	 * @return int|WP_Error
+	 * @return string
 	 */
 	protected function get_taxonomy( $request ) {
 		if ( '' !== $this->attribute ) {
diff --git a/includes/api/class-wc-rest-webhooks-controller.php b/includes/api/class-wc-rest-webhooks-controller.php
index a17f0657b12..46115b96be6 100644
--- a/includes/api/class-wc-rest-webhooks-controller.php
+++ b/includes/api/class-wc-rest-webhooks-controller.php
@@ -387,7 +387,6 @@ class WC_REST_Webhooks_Controller extends WC_REST_Posts_Controller {
 	/**
 	 * Prepare a single webhook output for response.
 	 *
-	 * @param WP_Post $webhook Webhook object.
 	 * @param WP_REST_Request $request Request object.
 	 * @return WP_REST_Response $response Response data.
 	 */
diff --git a/includes/class-wc-countries.php b/includes/class-wc-countries.php
index 55e5c1edb7c..7343fba44f8 100644
--- a/includes/class-wc-countries.php
+++ b/includes/class-wc-countries.php
@@ -64,7 +64,7 @@ class WC_Countries {
 	/**
 	 * Get continent code for a country code.
 	 * @since 2.6.0
-	 * @param $cc string
+	 * @param string $cc string
 	 * @return string
 	 */
 	public function get_continent_code_for_country( $cc ) {
diff --git a/includes/class-wc-install.php b/includes/class-wc-install.php
index 2213e3f987b..6c49005d271 100644
--- a/includes/class-wc-install.php
+++ b/includes/class-wc-install.php
@@ -240,6 +240,7 @@ class WC_Install {
 
 	/**
 	 * Update DB version to current.
+	 * @param string $version
 	 */
 	public static function update_db_version( $version = null ) {
 		delete_option( 'woocommerce_db_version' );
diff --git a/includes/class-wc-payment-tokens.php b/includes/class-wc-payment-tokens.php
index f3ec84cc555..6b31904ec50 100644
--- a/includes/class-wc-payment-tokens.php
+++ b/includes/class-wc-payment-tokens.php
@@ -76,7 +76,7 @@ class WC_Payment_Tokens {
 	 * Returns an array of payment token objects associated with the passed customer ID.
 	 * @since 2.6.0
 	 * @param  int    $customer_id  Customer ID
-	 * @param  string $gateway      Optional Gateway ID for getting tokens for a specific gateway
+	 * @param  string $gateway_id      Optional Gateway ID for getting tokens for a specific gateway
 	 * @return array                Array of token objects
 	 */
 	public static function get_customer_tokens( $customer_id, $gateway_id = '' ) {
diff --git a/includes/class-wc-shipping-rate.php b/includes/class-wc-shipping-rate.php
index 13412ddf492..6b4e80354b9 100644
--- a/includes/class-wc-shipping-rate.php
+++ b/includes/class-wc-shipping-rate.php
@@ -44,7 +44,7 @@ class WC_Shipping_Rate {
 	 *
 	 * @param string $id
 	 * @param string $label
-	 * @param float $cost
+	 * @param integer $cost
 	 * @param array $taxes
 	 * @param string $method_id
 	 */
@@ -87,8 +87,6 @@ class WC_Shipping_Rate {
 	/**
 	 * Get all meta data for this rate.
 	 * @since 2.6.0
-	 * @param string $key
-	 * @param string $value
 	 */
 	public function get_meta_data() {
 		return $this->meta_data;
diff --git a/includes/class-wc-shipping-zones.php b/includes/class-wc-shipping-zones.php
index cd580090767..3820b17a797 100644
--- a/includes/class-wc-shipping-zones.php
+++ b/includes/class-wc-shipping-zones.php
@@ -82,7 +82,6 @@ class WC_Shipping_Zones {
 	/**
 	 * Get shipping zone using it's ID
 	 * @since 2.6.0
-	 * @param int $zone_id
 	 * @return WC_Shipping_Meethod|bool
 	 */
 	public static function get_shipping_method( $instance_id ) {
diff --git a/includes/emails/class-wc-email.php b/includes/emails/class-wc-email.php
index f3d734dc69d..4de9798c97c 100644
--- a/includes/emails/class-wc-email.php
+++ b/includes/emails/class-wc-email.php
@@ -284,7 +284,7 @@ class WC_Email extends WC_Settings_API {
 	/**
 	 * Get email attachments.
 	 *
-	 * @return string|array
+	 * @return string
 	 */
 	public function get_attachments() {
 		return apply_filters( 'woocommerce_email_attachments', array(), $this->id, $this->object );
diff --git a/includes/wc-core-functions.php b/includes/wc-core-functions.php
index a9fb6246794..ea2d495925c 100644
--- a/includes/wc-core-functions.php
+++ b/includes/wc-core-functions.php
@@ -209,6 +209,7 @@ function wc_get_template( $template_name, $args = array(), $template_path = '',
  * Like wc_get_template, but returns the HTML instead of outputting.
  * @see wc_get_template
  * @since 2.5.0
+ * @param string $template_name
  */
 function wc_get_template_html( $template_name, $args = array(), $template_path = '', $default_path = '' ) {
 	ob_start();
@@ -1230,7 +1231,7 @@ function wc_help_tip( $tip, $allow_html = false ) {
  * Return a list of potential postcodes for wildcard searching.
  * @since 2.6.0
  * @param  string $postcode
- * @return array
+ * @return string[]
  */
 function wc_get_wildcard_postcodes( $postcode ) {
 	$postcodes         = array( '*', strtoupper( $postcode ), strtoupper( $postcode ) . '*' );
@@ -1252,6 +1253,7 @@ function wc_get_wildcard_postcodes( $postcode ) {
  * @param array $objects Array of postcode objects from Database
  * @param string $object_compare_key DB column name for the ID.
  * @param string $object_compare_key DB column name for the value.
+ * @param string $object_id_key
  * @return array Array of matching object ID and values.
  */
 function wc_postcode_location_matcher( $postcode, $objects, $object_id_key, $object_compare_key ) {
diff --git a/includes/wc-product-functions.php b/includes/wc-product-functions.php
index 9637bfd3198..15b198f16ce 100644
--- a/includes/wc-product-functions.php
+++ b/includes/wc-product-functions.php
@@ -706,7 +706,6 @@ function wc_get_product_cat_ids( $product_id ) {
 /**
  * Gets data about an attachment, such as alt text and captions.
  * @since 2.6.0
- * @param int $thumbnail_id
  * @param object|bool $product
  * @return array
  */
diff --git a/includes/wc-term-functions.php b/includes/wc-term-functions.php
index 7839a0f5604..c0513a90ef4 100644
--- a/includes/wc-term-functions.php
+++ b/includes/wc-term-functions.php
@@ -307,7 +307,7 @@ function add_woocommerce_term_meta( $term_id, $meta_key, $meta_value, $unique =
  *
  * @todo These functions should be deprecated with notices in a future WC version, allowing users a chance to upgrade WordPress.
  * @param mixed $term_id
- * @param mixed $meta_key
+ * @param string $meta_key
  * @param string $meta_value (default: '')
  * @param bool $deprecated (default: false)
  * @return bool
@@ -689,7 +689,6 @@ function wc_get_term_product_ids( $term_id, $taxonomy ) {
 
 /**
  * When a post is updated and terms recounted (called by _update_post_term_count), clear the ids.
- * @param int $term_id
  * @param int    $object_id  Object ID.
  * @param array  $terms      An array of object terms.
  * @param array  $tt_ids     An array of term taxonomy IDs.
diff --git a/includes/wc-user-functions.php b/includes/wc-user-functions.php
index 3005692b3e1..8b668a12127 100644
--- a/includes/wc-user-functions.php
+++ b/includes/wc-user-functions.php
@@ -628,7 +628,7 @@ function wc_get_customer_saved_methods_list( $customer_id ) {
  *
  * @since 2.6.0
  * @param int $customer_id Customer ID.
- * @return WC_Order|bool Order object if successful or false.
+ * @return WC_Order Order object if successful or false.
  */
 function wc_get_customer_last_order( $customer_id ) {
 	global $wpdb;