=> 'string',
					'context'     => array( 'view', 'edit' ),
				),
				'description'        => array(
					'description' => __( 'Payment gateway description on checkout.', 'woocommerce' ),
					'type'        => 'string',
					'context'     => array( 'view', 'edit' ),
				),
				'order'              => array(
					'description' => __( 'Payment gateway sort order.', 'woocommerce' ),
					'type'        => 'integer',
					'context'     => array( 'view', 'edit' ),
					'arg_options' => array(
						'sanitize_callback' => 'absint',
					),
				),
				'enabled'            => array(
					'description' => __( 'Payment gateway enabled status.', 'woocommerce' ),
					'type'        => 'boolean',
					'context'     => array( 'view', 'edit' ),
				),
				'method_title'       => array(
					'description' => __( 'Payment gateway method title.', 'woocommerce' ),
					'type'        => 'string',
					'context'     => array( 'view', 'edit' ),
					'readonly'    => true,
				),
				'method_description' => array(
					'description' => __( 'Payment gateway method description.', 'woocommerce' ),
					'type'        => 'string',
					'context'     => array( 'view', 'edit' ),
					'readonly'    => true,
				),
				'method_supports'    => array(
					'description' => __( 'Supported features for this payment gateway.', 'woocommerce' ),
					'type'        => 'array',
					'context'     => array( 'view', 'edit' ),
					'readonly'    => true,
					'items'       => array(
						'type' => 'string',
					),
				),
				'settings'           => array(
					'description' => __( 'Payment gateway settings.', 'woocommerce' ),
					'type'        => 'object',
					'context'     => array( 'view', 'edit' ),
					'properties'  => array(
						'id'          => array(
							'description' => __( 'A unique identifier for the setting.', 'woocommerce' ),
							'type'        => 'string',
							'context'     => array( 'view', 'edit' ),
							'readonly'    => true,
						),
						'label'       => array(
							'description' => __( 'A human readable label for the setting used in interfaces.', 'woocommerce' ),
							'type'        => 'string',
							'context'     => array( 'view', 'edit' ),
							'readonly'    => true,
						),
						'description' => array(
							'description' => __( 'A human readable description for the setting used in interfaces.', 'woocommerce' ),
							'type'        => 'string',
							'context'     => array( 'view', 'edit' ),
							'readonly'    => true,
						),
						'type'        => array(
							'description' => __( 'Type of setting.', 'woocommerce' ),
							'type'        => 'string',
							'context'     => array( 'view', 'edit' ),
							'enum'        => array( 'text', 'email', 'number', 'color', 'password', 'textarea', 'select', 'multiselect', 'radio', 'image_width', 'checkbox' ),
							'readonly'    => true,
						),
						'value'       => array(
							'description' => __( 'Setting value.', 'woocommerce' ),
							'type'        => 'string',
							'context'     => array( 'view', 'edit' ),
						),
						'default'     => array(
							'description' => __( 'Default value for the setting.', 'woocommerce' ),
							'type'        => 'string',
							'context'     => array( 'view', 'edit' ),
							'readonly'    => true,
						),
						'tip'         => array(
							'description' => __( 'Additional help text shown to the user about the setting.', 'woocommerce' ),
							'type'        => 'string',
							'context'     => array( 'view', 'edit' ),
							'readonly'    => true,
						),
						'placeholder' => array(
							'description' => __( 'Placeholder text to be displayed in text inputs.', 'woocommerce' ),
							'type'        => 'string',
							'context'     => array( 'view', 'edit' ),
							'readonly'    => true,
						),
					),
				),
			),
		);

		return $this->add_additional_fields_schema( $schema );
	}
}
<br />
<b>Fatal error</b>:  Uncaught Error: Class 'WC_REST_Payment_Gateways_Controller' not found in /home/mpir1/public_html/wp-content/plugins/woocommerce/includes/rest-api/Server.php:42
Stack trace:
#0 /home/mpir1/public_html/wp-includes/class-wp-hook.php(308): Automattic\WooCommerce\RestApi\Server-&gt;register_rest_routes(Object(WP_REST_Server))
#1 /home/mpir1/public_html/wp-includes/class-wp-hook.php(332): WP_Hook-&gt;apply_filters(NULL, Array)
#2 /home/mpir1/public_html/wp-includes/plugin.php(517): WP_Hook-&gt;do_action(Array)
#3 /home/mpir1/public_html/wp-includes/rest-api.php(577): do_action('rest_api_init', Object(WP_REST_Server))
#4 /home/mpir1/public_html/wp-includes/rest-api.php(403): rest_get_server()
#5 /home/mpir1/public_html/wp-includes/class-wp-hook.php(308): rest_api_loaded(Object(WP))
#6 /home/mpir1/public_html/wp-includes/class-wp-hook.php(332): WP_Hook-&gt;apply_filters(NULL, Array)
#7 /home/mpir1/public_html/wp-includes/plugin.php(565): WP_Hook-&gt;do_action(Array)
#8 /home/mpir1/public_html/wp-includes/class-wp.php(399): do_actio in <b>/home/mpir1/public_html/wp-content/plugins/woocommerce/includes/rest-api/Server.php</b> on line <b>42</b><br />