public function get_item_schema() {
		if ( $this->schema ) {
			return $this->add_additional_fields_schema( $this->schema );
		}

		$schema = array(
			'$schema'    => 'http://json-schema.org/draft-04/schema#',
			'title'      => 'comment',
			'type'       => 'object',
			'properties' => array(
				'id'                => array(
					'description' => __( 'Unique identifier for the object.' ),
					'type'        => 'integer',
					'context'     => array( 'view', 'edit', 'embed' ),
					'readonly'    => true,
				),
				'author'            => array(
					'description' => __( 'The ID of the user object, if author was a user.' ),
					'type'        => 'integer',
					'context'     => array( 'view', 'edit', 'embed' ),
				),
				'author_email'      => array(
					'description' => __( 'Email address for the object author.' ),
					'type'        => 'string',
					'format'      => 'email',
					'context'     => array( 'edit' ),
					'arg_options' => array(
						'sanitize_callback' => array( $this, 'check_comment_author_email' ),
						'validate_callback' => null, // skip built-in validation of 'email'.
					),
				),
				'author_ip'         => array(
					'description' => __( 'IP address for the object author.' ),
					'type'        => 'string',
					'format'      => 'ip',
					'context'     => array( 'edit' ),
				),
				'author_name'       => array(
					'description' => __( 'Display name for the object author.' ),
					'type'        => 'string',
					'context'     => array( 'view', 'edit', 'embed' ),
					'arg_options' => array(
						'sanitize_callback' => 'sanitize_text_field',
					),
				),
				'author_url'        => array(
					'description' => __( 'URL for the object author.' ),
					'type'        => 'string',
					'format'      => 'uri',
					'context'     => array( 'view', 'edit', 'embed' ),
				),
				'author_user_agent' => array(
					'description' => __( 'User agent for the object author.' ),
					'type'        => 'string',
					'context'     => array( 'edit' ),
					'arg_options' => array(
						'sanitize_callback' => 'sanitize_text_field',
					),
				),
				'content'           => array(
					'description' => __( 'The content for the object.' ),
					'type'        => 'object',
					'context'     => array( 'view', 'edit', 'embed' ),
					'arg_options' => array(
						'sanitize_callback' => null, // Note: sanitization implemented in self::prepare_item_for_database()
						'validate_callback' => null, // Note: validation implemented in self::prepare_item_for_database()
					),
					'properties'  => array(
						'raw'      => array(
							'description' => __( 'Content for the object, as it exists in the database.' ),
							'type'        => 'string',
							'context'     => array( 'edit' ),
						),
						'rendered' => array(
							'description' => __( 'HTML content for the object, transformed for display.' ),
							'type'        => 'string',
							'context'     => array( 'view', 'edit', 'embed' ),
							'readonly'    => true,
						),
					),
				),
				'date'              => array(
					'description' => __( "The date the object was published, in the site's timezone." ),
					'type'        => 'string',
					'format'      => 'date-time',
					'context'     => array( 'view', 'edit', 'embed' ),
				),
				'date_gmt'          => array(
					'description' => __( 'The date the object was published, as GMT.' ),
					'type'        => 'string',
					'format'      => 'date-time',
					'context'     => array( 'view', 'edit' ),
				),
				'link'              => array(
					'description' => __( 'URL to the object.' ),
					'type'        => 'string',
					'format'      => 'uri',
					'context'     => array( 'view', 'edit', 'embed' ),
					'readonly'    => true,
				),
				'parent'            => array(
					'description' => __( 'The ID for the parent of the object.' ),
					'type'        => 'integer',
					'context'     => array( 'view', 'edit', 'embed' ),
					'default'     => 0,
				),
				'post'              => array(
					'description' => __( 'The ID of the associated post object.' ),
					'type'        => 'integer',
					'context'     => array( 'view', 'edit' ),
					'default'     => 0,
				),
				'status'            => array(
					'description' => __( 'State of the object.' ),
					'type'        => 'string',
					'context'     => array( 'view', 'edit' ),
					'arg_options' => array(
						'sanitize_callback' => 'sanitize_key',
					),
				),
				'type'              => array(
					'description' => __( 'Type of Comment for the object.' ),
					'type'        => 'string',
					'context'     => array( 'view', 'edit', 'embed' ),
					'readonly'    => true,
				),
			),
		);

		if ( get_option( 'show_avatars' ) ) {
			$avatar_properties = array();

			$avatar_sizes = rest_get_avatar_sizes();
			foreach ( $avatar_sizes as $size ) {
				$avatar_properties[ $size ] = array(
					/* translators: %d: Avatar image size in pixels. */
					'description' => sprintf( __( 'Avatar URL with image size of %d pixels.' ), $size ),
					'type'        => 'string',
					'format'      => 'uri',
					'context'     => array( 'embed', 'view', 'edit' ),
				);
			}

			$schema['properties']['author_avatar_urls'] = array(
				'description' => __( 'Avatar URLs for the object author.' ),
				'type'        => 'object',
				'context'     => array( 'view', 'edit', 'embed' ),
				'readonly'    => true,
				'properties'  => $avatar_properties,
			);
		}

		$schema['properties']['meta'] = $this->meta->get_field_schema();

		$this->schema = $schema;
		return $this->add_additional_fields_schema( $this->schema );
	}