WordPress at a glance
filter is not described

script_loader_tag filter-hook . WP 4.1.0

Filters the HTML script tag of an enqueued script.

Usage

add_filter( 'script_loader_tag', 'filter_function_name_9177', 10, 3 );
function filter_function_name_9177( $tag, $handle, $src ){
	// filter...

	return $tag;
}
$tag(string)
The <script> tag for the enqueued script.
$handle(string)
The script's registered handle.
$src(string)
The script's source URL.

Where the hook is called

WP_Scripts::do_item()
wp-includes/class.wp-scripts.php 357
$tag = apply_filters( 'script_loader_tag', $tag, $handle, $src );

Where the hook is used (in WP core)

Does not used.