WordPress at a glance
filter is not described

wp_title filter-hook . WP 2.0.0

Filters the text of the page title.

Usage

add_filter( 'wp_title', 'filter_function_name_1829', 10, 3 );
function filter_function_name_1829( $title, $sep, $seplocation ){
	// filter...

	return $title;
}
$title(string)
Page title.
$sep(string)
Title separator.
$seplocation(string)
Location of the separator (left or right).

Where the hook is called

wp_title()
wp_title
wp-includes/general-template.php 1221
$title = apply_filters( 'wp_title', $title, $sep, $seplocation );

Where the hook is used (in WP core)

wp-includes/default-filters.php 123
add_filter( $filter, 'wptexturize' );
wp-includes/default-filters.php 124
add_filter( $filter, 'convert_chars' );
wp-includes/default-filters.php 125
add_filter( $filter, 'esc_html' );
wp-includes/default-filters.php 130
add_filter( $filter, 'capital_P_dangit', 11 );