Solve "Item to big" error in Merchant center by removing Visual composer tags and html from description and making sure the text left is not to large.

remove-vs-description.php

<?php
function remove_vc_description( $attributes, $feed_id, $product_id ) {
	
	//remove VC code
	$clean_description = preg_replace("/\[(\/*)?vc_(.*?)\]/", '', $attributes['description'] );
	
	// Strip html from description attributes
  	// allow given tags with allowedTags
  	$allowedTags = "";
	$clean_description = strip_tags($clean_description, $allowedTags);
	
	// Check if the text is larger as the max 5000 characters that Google limits
	// If so strip the text
	$max_length = 500; // 5000 is the max but Google also adivses 500 for a better User experience.
	if (strlen($clean_description) > $max_length) 
	{
    		$clean_description = wordwrap($clean_description, $max_length);
    		$clean_description = substr($clean_description, 0, strpos($clean_description, "\n"));
	}
	
	$attributes['description'] = $clean_description;
	
	// IMPORTANT! Always return the $attributes
	return $attributes;
}
add_filter( 'wppfm_feed_item_value', 'remove_vc_description', 10, 3 );