WordPress at a glance
filter is not described

wp_tag_cloud filter-hook . WP 2.3.0

Filters the tag cloud output.

Usage

add_filter( 'wp_tag_cloud', 'filter_function_name_8033', 10, 2 );
function filter_function_name_8033( $return, $args ){
	// filter...

	return $return;
}
$return(string)
HTML output of the tag cloud.
$args(array)
An array of tag cloud arguments.

Where the hook is called

wp_tag_cloud()
wp-includes/category-template.php 715
$return = apply_filters( 'wp_tag_cloud', $return, $args );

Where the hook is used (in WP core)

Does not used.